Linux “$$”在ps命令中表示什么？

可能重复：

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问题>

$

的含义是什么？

它与

ps

命令无关，

$

被shell替换为其进程ID它与

ps

命令无关，

$

被shell替换为其进程ID为的shell。它是一个内置shell变量，保存

PID

进程ID。

它是一个内置shell变量，保存

PID

进程ID

$ ./cruncher & ./cruncher & ./cruncher &
$ ps -C cruncher -p $$ -o pid,state,cmd
PID S CMD
2588 S bash
2657 R /bin/sh ./cruncher
2658 R /bin/sh ./cruncher
2659 R /bin/sh ./cruncher

-C cmdlist      Select by command name.
                       This selects the processes whose executable name is
                       given in cmdlist.

-p pidlist      Select by PID.
                       This selects the processes whose process ID numbers
                       appear in pidlist.