也是精心编撰的题目

linux

重定向问题

这里有几个符号大致说明一下其作用

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管道

创建一个有名字的管道 mkpipe.

$ mkfifo --help                                                                                                                                                             
Usage: mkfifo [OPTION]... NAME...
Create named pipes (FIFOs) with the given NAMEs.

Mandatory arguments to long options are mandatory for short options too.
  -m, --mode=MODE    set file permission bits to MODE, not a=rw - umask
  -Z                   set the SELinux security context to default type
      --context[=CTX]  like -Z, or if CTX is specified then set the SELinux
                         or SMACK security context to CTX
      --help     display this help and exit
      --version  output version information and exit

GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Full documentation <https://www.gnu.org/software/coreutils/mkfifo>
or available locally via: info '(coreutils) mkfifo invocation'

流式文件处理

awk 和 sed