10 あまり知られていない効果的な Linux コマンド - パート IV
あまり知られていないシリーズを続けるこのシリーズの 4 番目の記事では、 いくつかの便利な面白いコマンドやアニメーションなコマンドを紹介します。ここからはあまり理論を使わずに実践的なセッションに入ります。
- あまり知られていない便利な 11 の Linux コマンド – パート I
- あまり知られていない 10 の Linux コマンド – パート 2
- Linux のあまり知られていない 10 のコマンド – パート 3
- あまり知られていない便利な Linux コマンド 10 個 - パート V
このシリーズの 4 番目の記事では、知っておく価値のある、あまり知られていない Linux コマンドをいくつか紹介します。これらのコマンドについてはすでにご存知かもしれませんが、あなたは経験豊富な Linux ユーザーであり、探索が大好きであることは間違いありません。
32. straceコマンド
strace は、Linux で主にトラブルシューティングの目的で使用されるデバッグ ツールです。デフォルトではシステムにインストールされていない可能性があり、必要なパッケージをapt またはyum する必要がある場合があります。
strace コマンドを使用してコマンドの実行をトレースします。
[~]# strace pwd
サンプル出力
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "7ELFexecve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
brk(0) = 0x728000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
....
strace コマンドは多くの引数を受け入れ、多くのオプションがあります。詳細については、マニュアルページを参照してください。
33. disown -a && exit コマンド
ほとんどのシステム管理者は、screen コマンドを使用して、端末のバックグラウンドで実行されているジョブを制御します。長時間実行されているジョブがあり、 ターミナルから切断したい場合は、screen コマンドを使用してそれを実行するとします。しかし、画面の使い方がわからない場合は、disown コマンドを使用して救出してください。
disown コマンドは、ターミナル セッションを閉じた後でもバックグラウンドでジョブを継続的に実行するために使用されます。 disown コマンドの構文は次のとおりです。
[~]# Command; disown -a && exit
ターミナルで長時間実行されているジョブを再度切り離すには、jobs コマンドを使用してジョブ番号を見つけ、次に disown %n を使用します。n はジョブ番号。実際にジョブが実行されていることを確認するには、ps または top コマンドを使用します。 nohup コマンドは、disown コマンドの代わりに使用できます。
34. getconf LONG_BIT コマンド
上記のコマンドは、マシンのアーキテクチャが32 ビットか64 ビットかを表示します。
[~]# getconf LONG_BIT
32
35. 端末に日付を表示する
以下のコマンドは、いくつかのコマンドを組み合わせたもので、スクリプトと言ったほうがよいでしょう。シェルやターミナルで作業している人にとって、GUI を使用せずに現在のシステム日付を確認するのは退屈な作業です。今日の日付を確認するには、「date」コマンドを入力する必要があります。
プロンプトで以下のコマンドを実行すると、 ターミナルの右上隅に日付と時刻が表示されます。
[~]# while sleep 1;do tput sc;tput cup 0 $(($(tput cols)-29));date;tput rc;done &
36.convertコマンド
チュートリアルを書いているとき、私は通常、多くの場合画像形式で出力を生成する必要があります。上記のコマンドの組み合わせでこれが行われます。 Tree コマンドの出力 (/etc/x11 ディレクトリ用) を画像形式で必要とします。ターミナルで私がやったことは次のとおりです。
:/etc/X11# tree | convert label:@- /home/avi/tree.png
上記のコマンドの出力は、指定された場所 (ここでは私のホーム ディレクトリ) に、tree.png として指定されたファイル名で表示されます。
37. watch -t -n1 “日付 +%T|figlet”
以前の記事「Linux の面白いコマンド 20 選」での「figlet」コマンドの説明を思い出してください。このコマンドは非常にクールでした。今回は「figlet」をパイプライン処理します。ターミナルにアニメーションのデジタル時計を表示します。
自分でチェックアウトしてください。 システムにfiglet がインストールされている必要があることを忘れないでください。apt または yum を実行して必要なパッケージをインストールしてください。
[~]# watch -t -n1 "date +%T|figlet"
サンプル出力
_ ___ ____ ___ _____ _ _ Fri Nov 29 10:29:34 GMT
/ |/ _ \ _|___ \ / _ \ _|___ /| || |
| | | | (_) __) | (_) (_) |_ \| || |_
| | |_| |_ / __/ \__, |_ ___) |__ _|
|_|\___/(_)_____| /_/(_)____/ |_|
38. host および dig コマンド
\host と \dig コマンドの知名度はそれほど高くありませんが、それでもあまり頻繁には使用されません。ホスト コマンドはDNS検索ユーティリティです。
[~]# host www.google.com
www.google.com has address 173.194.66.147
www.google.com has address 173.194.66.105
www.google.com has address 173.194.66.99
www.google.com has address 173.194.66.104
www.google.com has address 173.194.66.106
www.google.com has address 173.194.66.103
www.google.com has IPv6 address 2a00:1450:400c:c03::68
[~]# dig www.google.com
; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6_4.6 <<>> www.google.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<
39. dstatコマンド
dstat は、システム リソースに関する統計を生成する多用途ツールです。デフォルトでは、システムに「dstat」がインストールされていない可能性があります。この非常にカラフルで説明的なシステム リソース ジェネレーターを使用する前に、apt または yum を実行して「dstat」をインストールします。
[~]# dstat
40.bind -p コマンド
「bind -p」 コマンドは、BASH シェルで使用できるすべてのショートカットを表示します。
[~]# bind -p
サンプル出力
"\C-g": abort
"\C-x\C-g": abort
"\e\C-g": abort
"\C-j": accept-line
"\C-m": accept-line
# alias-expand-line (not bound)
# arrow-key-prefix (not bound)
# backward-byte (not bound)
"\C-b": backward-char
"\eOD": backward-char
"\e[D": backward-char
"\e!": complete-command
"\e/": complete-filename
"\": complete-hostname
"\e{": complete-into-braces
"\e~": complete-username
"\e$": complete-variable
# copy-backward-word (not bound)
# copy-forward-word (not bound)
# copy-region-as-kill (not bound)
....
....41. touch /forcefsck
上記のコマンドは、ルート ディレクトリの下に空のフォルダー「forcefsck」を作成します。これにより、次回の起動時に Linux システムがファイル システムをチェックするようになります。
[~]# touch /forcefsck
それは今のところすべてです。皆さんはこれらの「あまり知られていないコマンド」を気に入っていただいているため、シリーズを継続していきます。このシリーズの次の記事は間もなく公開される予定です。
それまではTecmint にご注目ください。コメントセクションに貴重なフィードバックをお寄せください。私たちに好意を持ってください。「いいね！」とシェアして、拡散にご協力ください。