// $Id$
/**
* @file waitpid_test.c
* @brief waitpid 测试例子
*
* <br>版权所有© 2004~2005，罗智勇<br>
* All rights reserved. <br>
*
* @version $Revision$
* @author 罗智勇
* @date 2006年10月13日 15:43:02
**/
#include <sys/wait.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
int main(int argc, const char* argv[])
{
int status = 0;
pid_t ret_pid;
pid_t child_pid;
const char* child_name = "test";
const char* default_child_argv[] = { child_name, 0 };
const char** child_argv = default_child_argv;
fprintf(stdout, "waitpid test. v1.0 ");
if(argc >= 2){
child_name = argv[1];
child_argv = &(argv[1]);
}else{
fprintf(stdout, "Useage : %s [app_name [app_param]] ", argv[0]);
}
pid_t pid;
pid = fork();
if ( pid < 0 ){
perror( "Error in fork " );
return -1;
} else if ( pid > 0 ){
// 父进程空间
child_pid = pid;
}else{
// 子进程空间
fprintf( stderr, "---------------------------------- ");
printf("Child PID is %ld ", (long) getpid());
#if 1
chdir( "/tmp" );
//设置文件权限掩码
umask( 0 );
execv( child_name, (char* const*)child_argv );
fprintf( stderr, "execv("%s"...) error. ", child_name);
return -1;
#else
if(argc == 1)
pause();/* Wait for signals */
_exit(atoi(argv[1]));
#endif
}
do{
ret_pid = waitpid( child_pid, &status, WUNTRACED|WCONTINUED ); // WNOHANG
fprintf( stderr, "---------------------------------- ");
if( ret_pid == -1 )
{
fprintf( stderr, "waitpid error : (%d)%s ", errno, strerror(errno) );
return -1;
}else if( ret_pid != child_pid ){
fprintf( stderr, "waitpid abnormal, wait %d, but return %d, return val = %d. Error : (%d)%s "
, child_pid , ret_pid, status
, errno, strerror(errno) );
return -1;
}
if( WIFEXITED( status ) )
{
status = WEXITSTATUS( status );
fprintf(stderr, "The child return. Return value = 0x%x ", status);
break;
}
else if(WIFSIGNALED(status))
{
fprintf( stderr, "Killed by signal 0x%x. Return value = 0x%x ", WTERMSIG(status), status);
#ifdef WCOREDUMP
if(WCOREDUMP(status))
fprintf( stderr, " The child produced a core dump. ");
#endif
break;
}
else if(WIFSTOPPED(status))
{
// 子进程暂停，继续等待
fprintf(stderr, "Stopped by signal %d ", WSTOPSIG(status));
}
else
{
#ifdef WIFCONTINUED
if(WIFCONTINUED(status))
fprintf( stderr, "(Continued. ");
else
#endif
{
// 子进程因为其它原因使 wait_pid 返回
fprintf(stderr, "waitpid exit. The reason is unknow. return value = 0x%x ", status);
}
}
}while(1);
return status;
}
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