Linux guard Service-Kill daemon

Kill a child process

After killing the daemon's subprocess, the process changes to a zombie process

 14087 ?        Ss     0:00 ./test4-1 14088 ?        S      0:00  \_ ./test4-1 14089 ?        S      0:00  \_ ./test4-1 14090 ?        S      0:00  \_ ./test4-1 14091 ?        S      0:00  \_ ./test4-1 14092 ?        S      0:00  \_ ./test4-1 14093 ?        S      0:00  \_ ./test4-1 14094 ?        S      0:00  \_ ./test4-1 14095 ?        S      0:00  \_ ./test4-1 14096 ?        S      0:00  \_ ./test4-1 14097 ?        S      0:00  \_ ./test4-1[[email protected] 04]# kill -9 14090[[email protected] 04]# ps -xf

After execution:

 14087 ?        Ss     0:00 ./test4-1 14088 ?        S      0:00  \_ ./test4-1 14089 ?        S      0:00  \_ ./test4-1 14090 ?        Z      0:00  \_ [test4-1] <defunct> 14091 ?        S      0:00  \_ ./test4-1 14092 ?        S      0:00  \_ ./test4-1 14093 ?        S      0:00  \_ ./test4-1 14094 ?        S      0:00  \_ ./test4-1 14095 ?        S      0:00  \_ ./test4-1 14096 ?        S      0:00  \_ ./test4-1 14097 ?        S      0:00  \_ ./test4-1[[email protected] 04]#

Kill the parent process

After the parent process of the daemon, the zombie process is released and normal child processes become normal processes

[[email protected] 04]# kill -9 14087[[email protected] 04]# ps -xf

The zombie process is gone.

 14088 ?        S      0:00 ./test4-1 14089 ?        S      0:00 ./test4-1 14091 ?        S      0:00 ./test4-1 14092 ?        S      0:00 ./test4-1 14093 ?        S      0:00 ./test4-1 14094 ?        S      0:00 ./test4-1 14095 ?        S      0:00 ./test4-1 14096 ?        S      0:00 ./test4-1 14097 ?        S      0:00 ./test4-1

Kill All Processes

Directly using the process name

pkill 进程名

Let the child process end together with the parent process

Use Prctl to listen for the deathsig of the parent process after the process is created

for (i = 0; i < 10; i++) {    sleep(3);    printf("new fork() process pid = %d \n", pid);    pid = fork();    if (pid == 0) {            prctl(PR_SET_PDEATHSIG,SIGKILL);            break;    }}

When the parent process dies, the child process automatically receives the signal and ends without generating a zombie process and an orphan process

 14508 ?        Ss     0:00 ./test4-2 14509 ?        S      0:00  \_ ./test4-2 14510 ?        S      0:00  \_ ./test4-2 14511 ?        S      0:00  \_ ./test4-2 14512 ?        S      0:00  \_ ./test4-2 14513 ?        S      0:00  \_ ./test4-2 14514 ?        S      0:00  \_ ./test4-2 14515 ?        S      0:00  \_ ./test4-2 14516 ?        S      0:00  \_ ./test4-2 14517 ?        S      0:00  \_ ./test4-2 14518 ?        S      0:00  \_ ./test4-2[[email protected] 04]# kill -9 14508[[email protected] 04]# ps -xf  6786 ?        S      0:00 /usr/libexec/gconfd-2[[email protected] 04]# [[email protected] 04]# [[email protected] 04]#

Linux guard Service-Kill daemon