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SwimmingTiger/nc-not-works.log.c

Last active October 5, 2017 07:43
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logs of running `strace nc -l 4444`. (the `.c` postfix only for highlight)
Raw
nc-not-works.log.c
execve("/bin/nc", ["nc", "-l", "4444"], [/* 15 vars */]) = 0
brk(NULL) = 0xd42000
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) = 0x7fcaae0b0000
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=20683, ...}) = 0
mmap(NULL, 20683, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fcaae0b7000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libbsd.so.0", 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\0\0004\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=81040, ...}) = 0
mmap(NULL, 2179952, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fcaadbe0000
mprotect(0x7fcaadbf3000, 2093056, PROT_NONE) = 0
mmap(0x7fcaaddf2000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x12000) = 0x7fcaaddf2000
mmap(0x7fcaaddf4000, 880, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fcaaddf4000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libresolv.so.2", 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\0P9\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=101200, ...}) = 0
mmap(NULL, 2206280, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fcaad9c0000
mprotect(0x7fcaad9d7000, 2097152, PROT_NONE) = 0
mmap(0x7fcaadbd7000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x17000) = 0x7fcaadbd7000
mmap(0x7fcaadbd9000, 6728, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fcaadbd9000
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, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fcaae0a0000
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fcaad5f0000
mprotect(0x7fcaad7b0000, 2097152, PROT_NONE) = 0
mmap(0x7fcaad9b0000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c0000) = 0x7fcaad9b0000
mmap(0x7fcaad9b6000, 14752, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fcaad9b6000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fcaae090000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fcaae080000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fcaae070000
arch_prctl(ARCH_SET_FS, 0x7fcaae080700) = 0
mprotect(0x7fcaad9b0000, 16384, PROT_READ) = 0
mprotect(0x7fcaadbd7000, 4096, PROT_READ) = 0
mprotect(0x7fcaaddf2000, 4096, PROT_READ) = 0
mprotect(0x606000, 4096, PROT_READ) = 0
mprotect(0x7fcaae025000, 4096, PROT_READ) = 0
munmap(0x7fcaae0b7000, 20683) = 0
brk(NULL) = 0xd42000
brk(0xd63000) = 0xd63000
socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) = 3
setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
bind(3, {sa_family=AF_INET, sin_port=htons(4444), sin_addr=inet_addr("0.0.0.0")}, 16) = 0
listen(3, 1) = 0
accept(3, 0x7ffff91172c0, 0x7ffff9117234) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGTERM {si_signo=SIGTERM, si_code=SI_USER, si_pid=27, si_uid=0} ---
+++ killed by SIGTERM +++
Raw
nc-works-fine.log.c
execve("/bin/nc", ["nc", "-l", "4444"], [/* 24 vars */]) = 0
brk(NULL) = 0xc1f000
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) = 0x7fc42f840000
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=71972, ...}) = 0
mmap(NULL, 71972, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fc42f82e000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libbsd.so.0", 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\0\0004\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=81040, ...}) = 0
mmap(NULL, 2179952, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc42f3e0000
mprotect(0x7fc42f3f3000, 2093056, PROT_NONE) = 0
mmap(0x7fc42f5f2000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x12000) = 0x7fc42f5f2000
mmap(0x7fc42f5f4000, 880, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fc42f5f4000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libresolv.so.2", 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\0P9\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0644, st_size=101200, ...}) = 0
mmap(NULL, 2206280, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc42f1c0000
mprotect(0x7fc42f1d7000, 2097152, PROT_NONE) = 0
mmap(0x7fc42f3d7000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x17000) = 0x7fc42f3d7000
mmap(0x7fc42f3d9000, 6728, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fc42f3d9000
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, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fc42f820000
mmap(NULL, 3971488, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc42edf0000
mprotect(0x7fc42efb0000, 2097152, PROT_NONE) = 0
mmap(0x7fc42f1b0000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c0000) = 0x7fc42f1b0000
mmap(0x7fc42f1b6000, 14752, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fc42f1b6000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fc42f810000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fc42f800000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fc42f7f0000
arch_prctl(ARCH_SET_FS, 0x7fc42f800700) = 0
mprotect(0x7fc42f1b0000, 16384, PROT_READ) = 0
mprotect(0x7fc42f3d7000, 4096, PROT_READ) = 0
mprotect(0x7fc42f5f2000, 4096, PROT_READ) = 0
mprotect(0x606000, 4096, PROT_READ) = 0
mprotect(0x7fc42f825000, 4096, PROT_READ) = 0
munmap(0x7fc42f82e000, 71972) = 0
brk(NULL) = 0xc1f000
brk(0xc40000) = 0xc40000
socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) = 3
setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
bind(3, {sa_family=AF_INET, sin_port=htons(4444), sin_addr=inet_addr("0.0.0.0")}, 16) = 0
listen(3, 1) = 0
accept(3, {sa_family=AF_INET, sin_port=htons(12254), sin_addr=inet_addr("127.0.0.1")}, [16]) = 4
close(3) = 0
poll([{fd=4, events=POLLIN}, {fd=0, events=POLLIN}], 2, -1) = 1 ([{fd=4, revents=POLLIN}])
read(4, "hello\r\n", 2048) = 7
write(1, "hello\r\n", 7hello
) = 7
poll([{fd=4, events=POLLIN}, {fd=0, events=POLLIN}], 2, -1) = 1 ([{fd=4, revents=POLLIN}])
read(4, "", 2048) = 0
shutdown(4, SHUT_RD) = 0
close(4) = 0
close(3) = -1 EBADF (Bad file descriptor)
close(3) = -1 EBADF (Bad file descriptor)
exit_group(0) = ?
+++ exited with 0 +++
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