我正在尝试编写一个.sh文件,同时运行许多程序

我试过了

prog1 
prog2

但是它会运行prog1,然后等待prog1结束,然后启动prog2……

那么如何并行运行呢?


当前回答

你可以使用wait:

some_command &
P1=$!
other_command &
P2=$!
wait $P1 $P2

它将后台程序pid分配给变量($!是最后启动进程的PID),然后wait命令等待它们。这很好,因为如果您终止了脚本,它也会终止进程!

其他回答

我最近遇到了类似的情况,我需要同时运行多个程序,将它们的输出重定向到独立的日志文件中,然后等待它们完成,最后我得到了这样的结果:

#!/bin/bash

# Add the full path processes to run to the array
PROCESSES_TO_RUN=("/home/joao/Code/test/prog_1/prog1" \
                  "/home/joao/Code/test/prog_2/prog2")
# You can keep adding processes to the array...

for i in ${PROCESSES_TO_RUN[@]}; do
    ${i%/*}/./${i##*/} > ${i}.log 2>&1 &
    # ${i%/*} -> Get folder name until the /
    # ${i##*/} -> Get the filename after the /
done

# Wait for the processes to finish
wait

来源:http://joaoperibeiro.com/execute-multiple-programs-and-redirect-their-outputs-linux/

下面是我为了并行运行最多n个进程而使用的函数(示例中n=4):

max_children=4

function parallel {
  local time1=$(date +"%H:%M:%S")
  local time2=""

  # for the sake of the example, I'm using $2 as a description, you may be interested in other description
  echo "starting $2 ($time1)..."
  "$@" && time2=$(date +"%H:%M:%S") && echo "finishing $2 ($time1 -- $time2)..." &

  local my_pid=$$
  local children=$(ps -eo ppid | grep -w $my_pid | wc -w)
  children=$((children-1))
  if [[ $children -ge $max_children ]]; then
    wait -n
  fi
}

parallel sleep 5
parallel sleep 6
parallel sleep 7
parallel sleep 8
parallel sleep 9
wait

如果max_children被设置为核数,该函数将尝试避免空闲核。

这对我来说非常有用(在这里找到):

sh -c 'command1 & command2 & command3 & wait'

它混合输出每个命令的所有日志(这是我想要的),并使用ctrl+c杀死所有日志。

如何:

prog1 & prog2 && fg

这将:

prog1开始。 将其发送到后台,但继续打印其输出。 启动prog2,并将其放在前台,因此可以使用ctrl-c关闭它。 当你关闭prog2时,你将返回到prog1的前台,所以你也可以用ctrl-c关闭它。

这里有很多有趣的答案,但我从这个答案中获得了灵感,并将一个简单的脚本组合在一起,并行运行多个进程,并在完成后处理结果。你可以在以下要点中找到它:

#!/usr/bin/env bash

# inspired by https://stackoverflow.com/a/29535256/2860309

pids=""
failures=0

function my_process() {
    seconds_to_sleep=$1
    exit_code=$2
    sleep "$seconds_to_sleep"
    return "$exit_code"
}

(my_process 1 0) &
pid=$!
pids+=" ${pid}"
echo "${pid}: 1 second to success"

(my_process 1 1) &
pid=$!
pids+=" ${pid}"
echo "${pid}: 1 second to failure"

(my_process 2 0) &
pid=$!
pids+=" ${pid}"
echo "${pid}: 2 seconds to success"

(my_process 2 1) &
pid=$!
pids+=" ${pid}"
echo "${pid}: 2 seconds to failure"

echo "..."

for pid in $pids; do
        if wait "$pid"; then
                echo "Process $pid succeeded"
        else
                echo "Process $pid failed"
                failures=$((failures+1))
        fi
done

echo
echo "${failures} failures detected"

结果是:

86400: 1 second to success
86401: 1 second to failure
86402: 2 seconds to success
86404: 2 seconds to failure
...
Process 86400 succeeded
Process 86401 failed
Process 86402 succeeded
Process 86404 failed

2 failures detected