bash - 为什么“grep”在使用/“/”时会出错？

Question

背景

我正在尝试获取使用执行的命令的 PID，sh -c并将其存储在变量中以备后用。

#!/bin/bash

execute() {
   CMDS="$1"

   # x-terminal-emulator executes the quoted text by executing 'sh -c "$CMDS"'
   # Which is why "ps ax | grep ..." is used to search for the PID that
   # matches "sh -c $CMDS"
   x-terminal-emulator -e "$CMDS" &> /dev/null 

   cmdsPID="$(ps ax | grep \"sh -c "$CMDS"\" | xargs | cut -d ' ' -f 1)"

   echo "$cmdsPID"
}

execute "apt full-upgrade -y"

⚠️ 错误

但是，在执行上述脚本时，它返回：grep: apt full-upgrade -y": No such file or directory，为什么？

标签： bashgrep

Answer 1

好的，所以我显然过度考虑了我需要转义引号才能使其工作的事实。然而，这正是我不应该做的！我只需要不转义的引号就可以了。

这是因为，正如@biffen指出的那样：

"至于错误：您出于某种未知原因转义引号，使它们成为非引号，从而将三个参数传递给 grep ("sh和) -c，apt full-upgrade -y"告诉它计算sh文件中 " 的数量apt full-upgrade -y"，并且它告诉你它找不到那个文件。 ”

#!/bin/bash

execute() {
    CMDS="$1"

    # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

    # x-terminal-emulator executes the quoted text by executing 'sh -c "$CMDS"'
    # Which is why "ps ax | grep ..." is used to search for the PID that
    # matches "sh -c $CMDS"
    x-terminal-emulator -e "$CMDS" &> /dev/null 

    cmdsPID="$(ps ax | grep -v "grep" | grep -v "S+" | grep "sh -c" | grep "$CMDS" | xargs | cut -d ' ' -f 1)"

    echo "$cmdsPID"
}

execute "apt full-upgrade -y"