Linux_命令备忘录

1. ps aux

PROCESS STATE CODES

Here are the different values that the s, stat and state output specifiers

(header "STAT" or "S") will display to describe the state of a process.

D    Uninterruptible sleep (usually IO)

R    Running or runnable (on run queue)

S    Interruptible sleep (waiting for an event to complete)

T    Stopped, either by a job control signal or because it is being traced.

W    paging (not valid since the 2.6.xx kernel)

X    dead (should never be seen)

Z    Defunct ("zombie") process, terminated but not reaped by its parent.

For BSD formats and when the stat keyword is used, additional characters may

be displayed:

<    high-priority (not nice to other users)

N    low-priority (nice to other users)

L    has pages locked into memory (for real-time and custom IO)

s    is a session leader

l    is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)

+    is in the foreground process group

2. od

od可以以8\10\16\ASCII\进制方式显示文件内容，举例：

od -t x1 -Ax -c main.c

x1表示以一个字节16进制为单位显示文件内容，Ax表示地址偏移是用16进制表示，c表示以ASCII字符方式显示

3. tar cvf - ~/downloads | tar xvf - -C /tmp

4. cat records.txt | tr " " "\n" | sort

5. strace / ltrace

strace可以用来打印系统调用; ltrace用来打印库函数调用，即使使用自定义的库，也可打印出被调用函数名

-T 显示单个syscall耗时

-p 挂载到正在运行的进程上

-s 设置结果中显示printf等中打印的字符串长度，默认32

6. nc 传文件

server端

tar czf - ./library.a | nc -l 11111

client端

nc ip port | tar zxvf -