以下通過兩種方法來根據進程名稱獲取pid
方法一
最簡單的方法是使用 pidof 命令
用法：pidof process_name
示例
官網的詳細用法如下：
NAME
pidof -- find the process ID of a running program.
SYNOPSIS
pidof [-s] [-c] [-n] [-x] [-m] [-o omitpid[,omitpid..]] [-o omitpid[,omitpid..]..] program [program..]
DESCRIPTION
Pidof finds the process id's (pids) of the named programs. It prints those id's on the standard output. This program is on some systems used in run-level change scripts, especially when
the system has a System-V like rc structure. In that case these scripts are located in /etc/rc?.d, where ? is the runlevel. If the system has a start-stop-daemon (8) program that should
be used instead.
OPTIONS
-s Single shot - this instructs the program to only return one pid.
-c Only return process ids that are running with the same root directory. This option is ignored for non-root users, as they will be unable to check the current root directory of
processes they do not own.
-n Avoid stat(2) system function call on all binaries which are located on network based file systems like NFS. Instead of using this option the the variable PIDOF_NETFS may be set
and exported.
-x Scripts too - this causes the program to also return process id's of shells running the named scripts.
-o omitpid
Tells pidof to omit processes with that process id. The special pid %PPID can be used to name the parent process of the pidof program, in other words the calling shell or shell
script.
-m When used with -o, will also omit any processes that have the same argv[0] and argv[1] as any explicitly omitted process ids. This can be used to avoid multiple shell scripts
concurrently calling pidof returning each other's pids.
EXIT STATUS
0 At least one program was found with the requested name.
1 No program was found with the requested name.
NOTES
pidof is actually the same program as killall5; the program behaves according to the name under which it is called.
When pidof is invoked with a full pathname to the program it should find the pid of, it is reasonably safe. Otherwise it is possible that it returns pids of running programs that happen
to have the same name as the program you're after but are actually other programs. Note that that the executable name of running processes is calculated with readlink(2), so symbolic
links to executables will also match.
方法二
可以使用ps命令
ps -fC process_name
過濾出pid
ps -fC process_name | sed '1d' | awk '{print $2}'
一個簡單的腳本測試一下一上兩種方法【腳本名稱：pid.sh】
#!/bin/bash
if [ $# -ne 1 ]
then
echo "Usage : sh pid.sh process_name"
exit 1
fi
PID=`pidof $1`
if [ -n "$PID" ]
then
echo "$1 pid is $PID"
else
echo "$1 process is not running!"
fi
echo "======================================="
PID=`ps -fC $1 | sed '1d' | awk '{print $2}'`
if [ -n "$PID" ]
then
echo "$1 pid is $PID"
else
echo "$1 process is not running!"
fi
exit 0
sh pid.sh mysqld
