#!/usr/bin/perl
use strict;
use warnings;

my $continue = 1;
$SIG{'TERM'}  = sub { $continue = 0; print "Caught TERM signal\n"; };
$SIG{'INT'} = sub { $continue = 0; print "Caught INT signal\n"; };

my $i = 0;
while ($continue) {
     #do stuff
     print "Hello,I am running " . ++$i . "\n";
     sleep 3;
}

所以这个脚本基本上每3秒打印一次.

然后,因为我想守护这个脚本,我也把这个bash脚本(也称为synpipe_server)放在/etc/init.d/中：

#!/bin/bash
# synpipe_server : This starts and stops synpipe_server
#
# chkconfig: 12345 12 88
# description: Monitors all production pipelines
# processname: synpipe_server
# pidfile: /var/run/synpipe_server.pid
# Source function library.
. /etc/rc.d/init.d/functions

pname="synpipe_server"
exe="/usr/sbin/synpipe_server"
pidfile="/var/run/${pname}.pid"
lockfile="/var/lock/subsys/${pname}"

[ -x $exe ] || exit 0

RETVAL=0

start() {
    echo -n "Starting $pname : "
    daemon ${exe}
    RETVAL=$?
    PID=$!
    echo
    [ $RETVAL -eq 0 ] && touch ${lockfile}
    echo $PID > ${pidfile}
}

stop() {
    echo -n "Shutting down $pname : "
    killproc ${exe}
    RETVAL=$?
    echo
    if [ $RETVAL -eq 0 ]; then
        rm -f ${lockfile}
        rm -f ${pidfile}
    fi
}

restart() {
    echo -n "Restarting $pname : "
    stop
    sleep 2
    start
}

case "$1" in
    start)
        start
    ;;
    stop)
        stop
    ;;
    status)
        status ${pname}
    ;;
    restart)
        restart
    ;;
    *)
        echo "Usage: $0 {start|stop|status|restart}"
    ;; esac

exit 0

所以,(如果我已经很好地理解了守护进程的文档),Perl脚本应该在后台运行,如果我执行,输出应该重定向到/ dev / null：

service synpipe_server start

但这是我得到的：

[root@master init.d]# service synpipe_server start
Starting synpipe_server : Hello,I am running 1
Hello,I am running 2
Hello,I am running 3
Hello,I am running 4
Caught INT signal
                                                           [  OK  ]
[root@master init.d]#

所以它启动Perl脚本但运行它而不将它从当前的终端会话中分离出来,我可以看到我的控制台中打印的输出……这实际上并不是我所期待的.此外,PID文件为空(或仅使用换行符,守护程序不返回pid).

有谁知道我做错了什么？

编辑：也许我应该说我在Red Hat机器上.

Scientific Linux SL release 5.4 (Boron)

如果不使用守护进程函数,我会使用类似的东西吗？

nohup ${exe} >/dev/null 2>&1 &

在init脚本中？