linux cmd misc
check kernel config on board
cat /proc/config.gz | gunzip
ps(show the command)
ps -a -ubuild -o pid,ppid,stat,command
PID PPID STAT COMMAND
17009 1 Ds -bash
17065 1 D ls --color=tty -al
17577 1 D /usr/java/jdk1.5.0_17/bin/java -Xmx512m -classpath /usr/local/a
17629 1 D /usr/java/jdk1.5.0_17/bin/java -Xmx512m -classpath /usr/local/a
console:/ # ps -eo uid,pid,ppid,pri,rtprio,ni,time,comm,cmd
UID PID PPID PRI RTPRIO NI TIME COMM CMD
0 1 0 19 - 0 00:00:02 init init
0 2 0 19 - 0 00:00:00 2 kthreadd
sort，以一行中的某列数字大小排序
console:/proc/4219 # pmap 4219 |sort -k2,2nr |head -n 10
total 5093020K
00000074c31f0000 2093396K r---- [anon:cfi shadow]
00000074665aa000 1048576K ----- [anon:libwebview reservation]
0000000076475000 524288K rw--- [anon:dalvik-free list large object space]
00000000277c0000 372992K rw--- [anon:dalvik-main space (region space)]
00000000725c7000 55996K ----- [anon:dalvik-non moving space]
0000000096475000 32768K rw--- [anon:dalvik-zygote-data-code-cache]
0000000098475000 32768K r---- [anon:dalvik-zygote-jit-code-cache]
000000009a475000 32768K rw-s- /memfd:/jit-cache (deleted)
000000009c475000 32768K r-xs- /memfd:/jit-cache (deleted)
上述-k代表以第二列来排序，n代表以数字来排序，r表示以相反的顺序来排。
ps -o option help
Command line field types:
ARGS CMDLINE minus initial path CMD Thread name (/proc/TID/stat:2)
CMDLINE Command line (argv[]) COMM EXE filename (/proc/PID/exe)
COMMAND EXE path (/proc/PID/exe) NAME Process name (PID's argv[0])
Process attribute field types:
S Process state:
R (running) S (sleeping) D (device I/O) T (stopped) t (trace stop)
X (dead) Z (zombie) P (parked) I (idle)
Also between Linux 2.6.33 and 3.13:
x (dead) K (wakekill) W (waking)
SCH Scheduling policy (0=other, 1=fifo, 2=rr, 3=batch, 4=iso, 5=idle)
STAT Process state (S) plus:
< high priority N low priority L locked memory
s session leader + foreground l multithreaded
%CPU Percentage of CPU time used %MEM RSS as % of physical memory
%VSZ VSZ as % of physical memory ADDR Instruction pointer
BIT 32 or 64 C Total %CPU used since start
CPU Which processor running on DIO Disk I/O
DREAD Data read from disk DWRITE Data written to disk
ELAPSED Elapsed time since PID start F Flags 1=FORKNOEXEC 4=SUPERPRIV
GID Group ID GROUP Group name
IO Data I/O LABEL Security label
MAJFL Major page faults MINFL Minor page faults
NI Niceness (static 19 to -20) PCY Android scheduling policy
PGID Process Group ID PID Process ID
PPID Parent Process ID PR Prio Reversed (dyn 39-0, RT)
PRI Priority (dynamic 0 to 139) PSR Processor last executed on
READ Data read RES Short RSS
RGID Real (before sgid) Group ID RGROUP Real (before sgid) group name
RSS Resident Set Size (DRAM pages) RTPRIO Realtime priority
RUID Real (before suid) user ID RUSER Real (before suid) user name
SHR Shared memory STIME Start time (ISO 8601)
SWAP Swap I/O SZ 4k pages to swap out
TCNT Thread count TID Thread ID
TIME CPU time consumed TIME+ CPU time (high precision)
TTY Controlling terminal UID User id
USER User name VIRT Virtual memory size
VSZ Virtual memory size (1k units) WCHAN Wait location in kernel
WRITE Data written
快速创建大文件cmd
fallocate -l 1G test_big.bin #创建一个1G的大文件test_big.bin
truncate -s 100M test_big.bin #调整test_big.bin的大小到100M
上述两个cmd因为并没有将数据持久化，所以没有IO，所以会立即完成
sed d option
匹配一个关键字并将这个关键所在的行删除
sed -i /"[wlan]"/ test.txt
-i选项表示直接在输入文件上操作，将命令执行后的结果写入输入文件