如何运行名为foo的命令，并在运行bash shell或者脚本的GNU/Linux下10秒后使其超时/中止？
如何在闹钟下运行命令？
您应该能够使用python/ruby/php或者perl来将闹钟计时器设置为shell命令超时。

Shell没有内置的用于超时的命令。

Shell命令的闹钟设置超时

让我们看看各种例子

Perl程序

这是一个示例perl代码：

perl -e 'alarm shift @ARGV; exec @ARGV' 5 foo arg1 arg2

您可以将其定义为shell函数：

alarm() { perl -e 'alarm shift; exec @ARGV' "$@"; }

并按如下方式调用它(在使foo命令无效之前等待20秒：)

alarm 20 foo arg1

示例Shell脚本来设置命令超时

您可以使用以下shell脚本为命令设置超时：

##########################################################################
# Shellscript:	timeout - set timeout for a command 
#               Alarm clock Set Timeout
# Author     :	Heiner Steven <[email protected]>
# Date       :	29.07.1999
# Category   :	File Utilities
# Requires   :	
# SCCS-Id.   :	@(#) timeout	1.3 03/03/18
##########################################################################
# Description
#    o	Runs a command, and terminates it (by sending a signal) after
#	a specified time period
#    o	This command first starts itself as a "watchdog" process in the
#	background, and then runs the specified command.
#	If the command did not terminate after the specified
#	number of seconds, the "watchdog" process will terminate
#	the command by sending a signal.
#
# Notes
#    o	Uses the internal command line argument "-p" to specify the
#	PID of the process to terminate after the timeout to the
#	"watchdog" process.
#    o	The "watchdog" process is invoked by the name "
wget https://www.theitroad.local/files/doalarm-0.1.7.tgz
", so
#	"
$ wget http://pilcrow.madison.wi.us/sw/doalarm-0.1.7.tgz
" must be a valid path to the script.
#    o	If this script runs in the environment of the login shell
#	(i.e. it was invoked using ". timeout command...") it will
#	terminate the login session.
##########################################################################
 
PN=`basename "
$ tar -zxvf doalarm-0.1.7.tg
"`			# Program name
VER='1.3'
 
TIMEOUT=5				# Default [seconds]
 
Usage () {
    echo >&2 "$PN - set timeout for a command, $VER
usage: $PN [-t timeout] command [argument ...]
     -t: timeout (in seconds, default is $TIMEOUT)"
    exit 1
}
 
Msg () {
    for MsgLine
    do echo "$PN: $MsgLine" >&2
    done
}
 
Fatal () { Msg "$@"; exit 1; }
 
while [ $# -gt 0 ]
do
    case "" in
	-p)	ParentPID=; shift;;	# Used internally!
	-t)	Timeout=""; shift;;
	--)	shift; break;;
	-h)	Usage;;
	-*)	Usage;;
	*)	break;;			# First file name
    esac
    shift
done
 
: ${Timeout:=$TIMEOUT}			# Set default [seconds]
 
if [ -z "$ParentPID" ]
then
    # This is the first invokation of this script.
    # Start "watchdog" process, and then run the command.
    [ $# -lt 1 ] && Fatal "please specify a command to execute"
    "
$ cd doalarm-0.1.7
$ make
$ ./doalarm
" -p $$ -t $Timeout &		# Start watchdog
    #echo >&2 "DEBUG: process id is $$"
    exec "$@"				# Run command
    exit 2				# NOT REACHED
else
    # We run in "watchdog" mode, $ParentPID contains the PID
    # of the process we should terminate after $Timeout seconds.
    [ $# -ne 0 ] && Fatal "please do not use -p option interactively"
 
    #echo >&2 "DEBUG: $$: parent PID to terminate is $ParentPID"
 
    exec >/dev/null 0<&1 2>&1	# Suppress error messages
    sleep $Timeout
    kill $ParentPID &&			# Give process time to terminate
    	(sleep 2; kill -1 $ParentPID) &&
	(sleep 2; kill -9 $ParentPID)
    exit 0
fi

doalarm C程序

使用wget命令或者curl命令下载doalarm程序

Error: missing required parameter
Usage: doalarm [-hr] [-t type] sec command [arg...]
Run command under an alarm clock.

Options:
-t          Type of timer: 'real' (SIGALRM), 'virtual' (SIGVTALRM),
    --timer= 'profile' (SIGPROF), 'cpu' (SIGXCPU).  Default 'real'.
-r --recur        Recurring alarm, every sec seconds.
-h --help         Show help text (this message).
    --version      Display version.

doalarm 0.1.7 (14 Dec 2001)

或者

$ doalarm 20 foo

使用tar命令解压缩程序

command1 arg1 & sleep 10 ; kill $!
/path/to/foo bar & sleep 5 ; kill $!

编译doalarm：

timeout DURATION COMMAND
timeout DURATION COMMAND arg1 arg2
timeout 1m ping theitroad.com

输出示例：

如下运行foo：

主警报器在即将发生的警报下执行命令fooo。
缺省秒数以秒为单位的实际秒数到期后(通常是致命的)SIGALRM到期。
可用的过程计时器有两种类型：间隔和限制。
有关计时器和各自的信号，请参见下面的选项。
间隔计时器可能仅发出警报一次，也可能会定期发出警报(-r)，每秒钟发出一次信号。
对于间隔计时器，零秒值将清除继承的警报(如果有)。
对于限制计时器，零将命令cpu限制提高到硬最大值(通常为无限制)。

如何在Linux或者Unix Shell中使命令超时

使用命令设置睡眠时间，&&条件sa如下：

超时命令timeout

GNU/Linux附带超时命令。
它运行一个有时间限制的命令。
本教程说明如何启动命令，以及在指定的超时时间到期时将其杀死：