前言
strace用來跟蹤進程的系統調用或信號產生的情況;
ltrace 用來跟蹤進程調用庫函數的情況。
1，strace命令
root@ubuntu:/opt/files/release/strace/x86_64/bin# ./strace uname
execve("/bin/uname", ["uname"], 0x7ffc0cd82290 /* 20 vars */) = 0
brk(NULL) = 0x1ed4000
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
access("/etc/ld.so.preload", R_OK) = 0
open("/etc/ld.so.preload", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=1, ...}) = 0
mmap(NULL, 1, PROT_READ|PROT_WRITE, MAP_PRIVATE, 3, 0) = 0x7f4fcdb37000
close(3) = 0
munmap(0x7f4fcdb37000, 1) = 0
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=85661, ...}) = 0
mmap(NULL, 85661, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f4fcdb23000
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\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P \2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1857312, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f4fcdb22000
mmap(NULL, 3965632, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f4fcd54d000
mprotect(0x7f4fcd70b000, 2097152, PROT_NONE) = 0
mmap(0x7f4fcd90b000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1be000) = 0x7f4fcd90b000
mmap(0x7f4fcd911000, 17088, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f4fcd911000
close(3) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f4fcdb20000
arch_prctl(ARCH_SET_FS, 0x7f4fcdb20740) = 0
mprotect(0x7f4fcd90b000, 16384, PROT_READ) = 0
mprotect(0x606000, 4096, PROT_READ) = 0
mprotect(0x7f4fcdb38000, 4096, PROT_READ) = 0
munmap(0x7f4fcdb23000, 85661) = 0
brk(NULL) = 0x1ed4000
brk(0x1ef5000) = 0x1ef5000
open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=7216688, ...}) = 0
mmap(NULL, 7216688, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f4fcce6b000
close(3) = 0
uname({sysname="Linux", nodename="ubuntu", ...}) = 0
fstat(1, {st_mode=S_IFCHR|0600, st_rdev=makedev(0x88, 0), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f4fcdb37000
write(1, "Linux\n", 6Linux
) = 6
close(1) = 0
munmap(0x7f4fcdb37000, 4096) = 0
close(2) = 0
exit_group(0) = ?
+++ exited with 0 +++
2，ltrace命令
root@ubuntu:/opt/files/release/ltrace/x86_64/bin# ./ltrace uname
__libc_start_main(0x401590, 1, 0x7ffdd645ee98, 0x4042c0 <unfinished ...>
strrchr("uname", '/') = nil
setlocale(LC_ALL, "") = "en_US.UTF-8"
bindtextdomain("coreutils", "/usr/share/locale") = "/usr/share/locale"
textdomain("coreutils") = "coreutils"
__cxa_atexit(0x401da0, 0, 0, 0x736c6974756572) = 0
getopt_long(1, 0x7ffdd645ee98, "asnrvmpio", 0x4049c0, nil) = -1
uname(0x7ffdd645e980) = 0
fputs_unlocked(0x7ffdd645e980, 0x7f5bce464400, 0x7f5bce463280, 0x7f5bce165827) = 1
__overflow(0x7f5bce464400, 10, 0x7f5bce68b004, 1024Linux
) = 10
exit(0 <unfinished ...>
__fpending(0x7f5bce464400, 0, 64, 0x7f5bce464eb0) = 0
fileno(0x7f5bce464400) = 1
__freading(0x7f5bce464400, 0, 64, 0x7f5bce464eb0) = 0
__freading(0x7f5bce464400, 0, 2052, 0x7f5bce464eb0) = 0
fflush(0x7f5bce464400) = 0
fclose(0x7f5bce464400) = 0
__fpending(0x7f5bce4641c0, 0, 0x7f5bce465900, 0xfbad000c) = 0
fileno(0x7f5bce4641c0) = 2
__freading(0x7f5bce4641c0, 0, 0x7f5bce465900, 0xfbad000c) = 0
__freading(0x7f5bce4641c0, 0, 4, 0xfbad000c) = 0
fflush(0x7f5bce4641c0) = 0
fclose(0x7f5bce4641c0) = 0
+++ exited (status 0) +++
3，總結
根據實際的需要，選擇合適的工具對程序進行分析，提高程序的健壯性。
4，參考
使用strace,lstrace,truss來跟蹤程序的運行過程 https://blog.csdn.net/liangzhao_jay/article/details/50457197