10 Strace komandas problēmu novēršanai un Linux procesu atkļūdošanai

strace ir spēcīgs komandrindas rīks programmu atkļūdošanai un problēmu novēršanai Unix līdzīgās operētājsistēmās, piemēram, Linux. Tas uztver un reģistrē visus procesa zvanus un procesa saņemtos signālus.

Tas parāda katra sistēmas izsaukuma nosaukumu kopā ar argumentiem, kas iekļauti iekavās, un tā atgriešanās vērtību pie standarta kļūdas; pēc izvēles varat to novirzīt arī failā.

Šajā rakstā mēs izskaidrosim 10 strace komandu piemērus programmu un procesu problēmu novēršanai un atkļūdošanai Linux sistēmā.

Kā instalēt Strace procesa uzraudzības rīku Linux

Ja jūsu Linux sistēmā strace nav iepriekš instalēta, izpildiet tālāk norādīto izplatīšanas komandu, lai to instalētu.

$ sudo apt install strace	#Debian/Ubuntu 
# yum install strace		#RHEL/CentOS
# dnf install strace		#Fedora 22+

Gadījumā, ja programma avarē vai darbojas tā, kā nav gaidīts, varat iziet cauri tās sistēmas zvaniem, lai uzzinātu, kas tieši notika tās izpildes laikā. Kā mēs redzēsim vēlāk, sistēmas izsaukumus var iedalīt dažādos notikumos: tie, kas attiecas uz procesu pārvaldību, tie, kas par argumentu uzskata failu, tie, kas ietver tīklu veidošanu, atmiņas kartēšanu, signālus, IPC un arī ar failu deskriptoriem saistītus sistēmas izsaukumus.

Varat vai nu palaist programmu/komandu ar strace, vai arī nodot tai PID, izmantojot opciju -p , kā parādīts turpmākajos piemēros.

1. Izsekojiet Linux komandu sistēmas izsaukumus

Jūs varat vienkārši palaist komandu ar šādu strace, šeit mēs izsekojam visus sistēmas zvanus, kurus veic komanda df.

$ strace df -h

execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "7ELF
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
$ strace df -h
execve("/bin/df", ["df", "-h"], [/* 50 vars */]) = 0
brk(NULL)                               = 0x136e000
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f82f78fd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f82f78d8000
close(3)                                = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f82f7310000
...
No iepriekš minētās izejas jūs varat redzēt dažāda veida sistēmas zvanus, piemēram, ar komandu df.
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
Kur:
 
 atvērts - ir sistēmas izsaukuma veids 
 
 (“/etc/ld.so.cache”, O_RDONLY | O_CLOEXEC) - sistēmas izsaukuma arguments 
 
 3 - sistēmas zvana atgriešanās vērtība 
 
Zemāk ir izejas paraugs, kurā parādīti rakstīšanas sistēmas izsaukumi, kas ekrānā parāda df komandu izvadi.
mmap(NULL, 26258, PROT_READ, MAP_SHARED, 3, 0) = 0x7f82f78f5000
close(3)                                = 0
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 1), ...}) = 0
write(1, "Filesystem      Size  Used Avail"..., 49Filesystem      Size  Used Avail Use% Mounted on
) = 49
write(1, "udev            3.9G     0  3.9G"..., 43udev            3.9G     0  3.9G   0% /dev
) = 43
write(1, "tmpfs           788M  9.6M  779M"..., 43tmpfs           788M  9.6M  779M   2% /run
) = 43
write(1, "/dev/sda10      324G  252G   56G"..., 40/dev/sda10      324G  252G   56G  82% /
) = 40
write(1, "tmpfs           3.9G  104M  3.8G"..., 47tmpfs           3.9G  104M  3.8G   3% /dev/shm
) = 47
write(1, "tmpfs           5.0M  4.0K  5.0M"..., 48tmpfs           5.0M  4.0K  5.0M   1% /run/lock
) = 48
write(1, "tmpfs           3.9G     0  3.9G"..., 53tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
) = 53
write(1, "cgmfs           100K     0  100K"..., 56cgmfs           100K     0  100K   0% /run/cgmanager/fs
) = 56
write(1, "tmpfs           788M   36K  788M"..., 53tmpfs           788M   36K  788M   1% /run/user/1000
) = 53
close(1)                                = 0
close(2)                                = 0
exit_group(0)                           = ?
+++ exited with 0 +++
2. Izsekot Linux procesa PID
Ja process jau darbojas, varat to izsekot, vienkārši nododot tā PID šādi: tas aizpildīs jūsu ekrānu ar nepārtrauktu izvadi, kas parāda procesa zvanus, kurus veic process, lai tos pārtrauktu, nospiediet  [Ctrl + C] .
$ sudo strace -p 3569

strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U0!70
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
$ sudo strace -p 3569
strace: Process 3569 attached
restart_syscall(<... resuming interrupted poll ...>) = 1
recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"U\2\24\300!\247\330\0\3\24\4\0\20\0\0\0\0\0\0\24\24\24\24\24\0\0\3\37%\2\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(4, 0x7ffee4dbf870, 0)           = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, -1) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 1 ([{fd=31, revents=POLLIN}])
read(31, "\372", 1)                     = 1
recvmsg(4, 0x7ffee4dbf850, 0)           = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=4, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN}, {fd=30, events=POLLIN}, {fd=31, events=POLLIN}], 6, 0) = 0 (Timeout)
mprotect(0x207faa20000, 8192, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa20000, 8192, PROT_READ|PROT_EXEC) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_WRITE) = 0
mprotect(0x207faa21000, 4096, PROT_READ|PROT_EXEC) = 0
...
3. Iegūstiet Linux procesa kopsavilkumu
Izmantojot karodziņu  -c , varat ģenerēt pārskatu par kopējo laiku, zvaniem un kļūdām katram sistēmas zvanam šādi.
$ sudo strace -c -p 3569

strace: Process 3569 attached

^Cstrace: Process 3569 detached
% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 99.73    0.016000           8      1971           poll
  0.16    0.000025           0       509        75 futex
  0.06    0.000010           0      1985      1966 recvmsg
  0.06    0.000009           0      2336           mprotect
  0.00    0.000000           0       478           read
  0.00    0.000000           0        13           write
  0.00    0.000000           0        29           mmap
  0.00    0.000000           0         9           munmap
  0.00    0.000000           0        18           writev
  0.00    0.000000           0       351           madvise
  0.00    0.000000           0         1           restart_syscall
------ ----------- ----------- --------- --------- ----------------
100.00    0.016044                  7700      2041 total
4. Drukāt instrukciju rādītāju sistēmas izsaukuma laikā
Opcija  -i  parāda instrukciju rādītāju katra programmas veiktā sistēmas zvana laikā.
$ sudo strace -i df -h

[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "7ELF
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
$ sudo strace -i df -h
[00007f0d7534c777] execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
[00007faf9cafa4b9] brk(NULL)            = 0x12f0000
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb47a] mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7faf9cd03000
[00007faf9cafb387] access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7faf9ccde000
[00007faf9cafb427] close(3)             = 0
[00007faf9cafb387] access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
[00007faf9cafb327] open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
[00007faf9cafb347] read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
[00007faf9cafb2b4] fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
[00007faf9cafb47a] mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7faf9c716000
[00007faf9cafb517] mprotect(0x7faf9c8d6000, 2097152, PROT_NONE) = 0
...
5. Rādīt dienas laiku katrai izsekošanas izvades līnijai
Varat arī izdrukāt dienas laiku katrai rindai izsekošanas izvadā, nokārtojot karodziņu  -t .
$ sudo strace -t df -h

15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "7ELF
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
$ sudo strace -t df -h
15:19:25 execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
15:19:25 brk(NULL)                      = 0x234c000
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8c7f1d9000
15:19:25 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
15:19:25 fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0
15:19:25 mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f8c7f1b4000
15:19:25 close(3)                       = 0
15:19:25 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
15:19:25 open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
15:19:25 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\t\2\0\0\0\0\0"..., 832) = 832
15:19:25 fstat(3, {st_mode=S_IFREG|0755, st_size=1868984, ...}) = 0
15:19:25 mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f8c7ebec000
15:19:25 mprotect(0x7f8c7edac000, 2097152, PROT_NONE) = 0
...
6. Sistēmas zvanos pavadītais komandas drukāšanas laiks


Lai parādītu laika starpību starp katra sistēmas veiktā sistēmas zvana sākumu un beigām, izmantojiet opciju  -T .
$ sudo strace -T df -h

execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0 <0.000287>
brk(NULL)                               = 0xeca000 <0.000035>
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory) <0.000028>
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9aff2b1000 <0.000020>
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory) <0.000019>
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3 <0.000022>
fstat(3, {st_mode=S_IFREG|0644, st_size=147662, ...}) = 0 <0.000015>
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f9aff28c000 <0.000019>
close(3)                                = 0 <0.000014>
...
7. Izsekot tikai īpašus sistēmas izsaukumus
Zemāk esošajā komandā  trace = write  ir pazīstams kā kvalificējošs izteiciens, kur trace ir kvalifikators (citi ietver signālu, saīsinājumu, izteiksmīgu, neapstrādātu, lasītu vai rakstītu). Šeit rakstīt ir kvalifikatora vērtība.
Šī komanda faktiski parāda sistēmas aicinājumus drukāt df izvadi uz standarta izvadi.
$ sudo strace -e trace=write df -h

write(1, "Filesystem      Size  Used Avail"..., 49Filesystem      Size  Used Avail Use% Mounted on
) = 49
write(1, "udev            3.9G     0  3.9G"..., 43udev            3.9G     0  3.9G   0% /dev
) = 43
write(1, "tmpfs           788M  9.6M  779M"..., 43tmpfs           788M  9.6M  779M   2% /run
) = 43
write(1, "/dev/sda10      324G  252G   56G"..., 40/dev/sda10      324G  252G   56G  82% /
) = 40
write(1, "tmpfs           3.9G  104M  3.8G"..., 47tmpfs           3.9G  104M  3.8G   3% /dev/shm
) = 47
write(1, "tmpfs           5.0M  4.0K  5.0M"..., 48tmpfs           5.0M  4.0K  5.0M   1% /run/lock
) = 48
write(1, "tmpfs           3.9G     0  3.9G"..., 53tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
) = 53
write(1, "cgmfs           100K     0  100K"..., 56cgmfs           100K     0  100K   0% /run/cgmanager/fs
) = 56
write(1, "tmpfs           788M   28K  788M"..., 53tmpfs           788M   28K  788M   1% /run/user/1000
) = 53
+++ exited with 0 +++
Šeit ir dažas papildu komandas par izsekošanas kvalifikatoru.
$ sudo strace -e trace=open,close df -h
$ sudo strace -e trace=open,close,read,write df -h
$ sudo strace -e trace=all df -h	
8. Izsekot sistēmas izsaukumus, pamatojoties uz noteiktu nosacījumu
Apskatīsim, kā izsekot sistēmas zvaniem, kas saistīti ar noteiktu notikumu klasi. Šo komandu var izmantot, lai izsekotu visiem sistēmas zvaniem, kas saistīti ar procesa pārvaldību.
$ sudo strace -q -e trace=process df -h	

execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
arch_prctl(ARCH_SET_FS, 0x7fe2222ff700) = 0
Filesystem      Size  Used Avail Use% Mounted on
udev            3.9G     0  3.9G   0% /dev
tmpfs           788M  9.6M  779M   2% /run
/dev/sda10      324G  252G   56G  82% /
tmpfs           3.9G  104M  3.8G   3% /dev/shm
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
cgmfs           100K     0  100K   0% /run/cgmanager/fs
tmpfs           788M   28K  788M   1% /run/user/1000
exit_group(0)                           = ?
+++ exited with 0 +++
Pēc tam, lai izsekotu visiem sistēmas izsaukumiem, kuru faila nosaukums ir arguments, palaidiet šo komandu.
$ sudo strace -q  -e trace=file df -h

execve("/bin/df", ["df", "-h"], [/* 17 vars */]) = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
open("/usr/share/locale/locale.alias", O_RDONLY|O_CLOEXEC) = 3
...
Lai izsekotu visiem sistēmas zvaniem, kas saistīti ar atmiņas kartēšanu, ierakstiet.
$ sudo strace -q -e trace=memory df -h	

brk(NULL)                               = 0x77a000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4658000
mmap(NULL, 147662, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe8f4633000
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fe8f406b000
mprotect(0x7fe8f422b000, 2097152, PROT_NONE) = 0
mmap(0x7fe8f442b000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c0000) = 0x7fe8f442b000
mmap(0x7fe8f4431000, 14752, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4431000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4632000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4631000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe8f4630000
mprotect(0x7fe8f442b000, 16384, PROT_READ) = 0
mprotect(0x616000, 4096, PROT_READ)     = 0
mprotect(0x7fe8f465a000, 4096, PROT_READ) = 0
munmap(0x7fe8f4633000, 147662)          = 0
mmap(NULL, 2981280, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe8f3d93000
brk(NULL)                               = 0x77a000
brk(0x79b000)                           = 0x79b000
mmap(NULL, 619, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fe8f4657000
mmap(NULL, 26258, PROT_READ, MAP_SHARED, 3, 0) = 0x7fe8f4650000
Filesystem      Size  Used Avail Use% Mounted on
udev            3.9G     0  3.9G   0% /dev
tmpfs           788M  9.6M  779M   2% /run
/dev/sda10      324G  252G   56G  82% /
tmpfs           3.9G  104M  3.8G   3% /dev/shm
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
cgmfs           100K     0  100K   0% /run/cgmanager/fs
tmpfs           788M   28K  788M   1% /run/user/1000
+++ exited with 0 +++
Jūs varat izsekot visiem ar tīklu un signāliem saistītajiem sistēmas zvaniem.
$ sudo strace -e trace=network df -h
$ sudo strace -e trace=signal df -h
9. Novirziet izsekošanas izvadi uz failu
Lai failā ierakstītu standarta kļūdas laikā nosūtītos izsekošanas ziņojumus, izmantojiet opciju  -o . Tas nozīmē, ka ekrānā tiek izdrukāta tikai komandu izeja, kā parādīts zemāk.
$ sudo strace -o df_debug.txt df -h

Filesystem      Size  Used Avail Use% Mounted on
udev            3.9G     0  3.9G   0% /dev
tmpfs           788M  9.6M  779M   2% /run
/dev/sda10      324G  252G   56G  82% /
tmpfs           3.9G  104M  3.8G   3% /dev/shm
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup
cgmfs           100K     0  100K   0% /run/cgmanager/fs
tmpfs           788M   28K  788M   1% /run/user/1000
Lai pārlūkotu failu, izmantojiet komandu cat.
$ cat df_debug.txt 
10. Parādiet kādu Strace atkļūdošanas rezultātu

Lai parādītu strace rīka atkļūdošanas informāciju, izmantojiet karodziņu  -d .
$ strace -d df -h
Papildinformāciju skatiet strace man lapā.
$ man strace
Izlasiet arī šos noderīgos saistītos rakstus:
 
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Noslēgumā jāsaka, ka strace ir ievērojams rīks programmas kļūmes cēloņu diagnosticēšanai: tā ir spēcīga atkļūdošana un problēmu novēršana. Tas ir praktiski noderīgi pieredzējušiem sistēmas administratoriem, programmētājiem un hakeriem. Lai dalītos domās par šo rakstu, izmantojiet tālāk sniegto atsauksmju veidlapu.