Question

如何在模式匹配之前阻塞管道？我想做这样的事情：

#!/bin/sh

mkfifo request response
while true; do # needs to send one response at a time
  nc -N -l 127.0.0.1 4000 >request <response & # send output to request pipe
  sed -u '/^$/q' <request; # block until a blank line is received
  date | tee response # send input back to the original command
done

Answer 1

如果匹配模式的操作是阻塞的，则可以使用cat来阻止数据从命名管道中出来，直到写入某些内容为止。 cat将从命名管道中读取数据，直到写入EOF。

#!/bin/sh

mkfifo response
while true; do # send one response at a time
  cat response | nc -N -l 127.0.0.1 4000 | # pipe request out
  (
    sed -u '/^$/q' # block until a blank line is received
    date | tee response # send input back to the original command
  )
done

如何在模式匹配之前阻止管道？

1 个答案: