&p指的是什么？

Question

我不能弄清楚&p在下面的脚本中做什么。print -u4是否意味着传递的任何参数都写在文件描述符4中?

1:  $SRVRMGRCMD |&
3:  BGPID=$!
4:  exec 4>&p
5:  exec 5<&p
6:  sleep 2
7:  # Build a list of Servers
8:  print -u4 "list servers show SBLSRVR_NAME"

Answer 1

这些似乎是对协同进程的引用(在ksh或zsh中)。
见https://unix.stackexchange.com/questions/86270/how-do-you-use-the-command-coproc-in-bash

Answer 2

这是什么语言?

如果是bash或shell，它会创建一个文件描述符来存储输出，见这里:

http://www.softpanorama.org/Tools/exec.shtml，特别是这一部分:

exec 3< inputfile   # Opens inputfile with file descriptor 3 for reading.
exec 4> outputfile  # Opens outputfile with file descriptor 4 for writing.
exec 5<&0   # Makes fd 5 a copy of fd 0 (standard input).
exec 6>&p   # Attach fd 6 to co-process.

编辑说:

-un表示将所有输出写入文件描述符n

http://alasir.com/books/bsd/428 - 430. - html