process.h

C语言库函数介绍

@函数名称:     spawnl、spawnle、spawnlp、spawnlpe、spawnv、spawnve、spawnvp、spawnvpe
函数原型:     int spawnl(int mode, char *path, char *arg 0, … )
	     int spawnle(int mode, char *path, char *arg0, … )
	     int spawnlp(int mode, char *path, char *arg0, … )
	     int spawnlpe(int mode, char *path, char *arg0, … )
	     int spawnv(int mode, char *path, char *argv[])
	     int spawnve(int mode, char *path, char *argv[], char **env)
	     int spawnvp(int mode, char *path, char *argv[])
	     int spawnvpe(int mode, char *path, char *argv[], char **env)
函数功能:     在一个程序中调用另外一个程序
函数返回:     -1:调用失败，0:调用成功
参数说明:     path-被调用程序路径，arg-调用的参数,mode-调用模式，具体如下：
		P_WAIT    0 将父过程挂起，直到子过程执行完毕
		P_NOWAIT  1 父子过程同时执行，Turboc不支持
		P_OVERLAY 2 子过程覆盖父过程
所属文件:     <process.h>

#include <stdio.h>
#include <stdlib.h>
#include <process.h>
#include <errno.h>
#include <string.h>

int main()
{
    int process_id;
#if defined(__OS2__)||defined(__NT__)
    int status, rc;
#endif

    process_id=spawnl(P_NOWAIT,"child.exe","child","5",NULL);
    if(process_id==-1){
        printf("spawn failed-%s\n",strerror(errno));
        exit(EXIT_FAILURE);
    }
    printf("Process id=%d\n",process_id);

#if defined(__OS2__)||defined(__NT__)
    rc=cwait(&status,process_id,WAIT_CHILD);
    if(rc==-1){
        printf("wait failed-%s\n",strerror(errno));
    }else{
        printf("wait succeeded-%x\n",status);
        switch(status&0xff){
        case 0:
            printf("Normal termination code=%d\n",status>>8);
            break;
        case 1:
            printf("Hard-error abort\n");
            break;
        case 2:
            printf("Trap operation\n");
            break;
        case 3:
            printf("SIGTERM signal not intercepted\n");
            break;
        default:
            printf("Bogus return status\n");
        }
    }
#endif
    printf("spawn completed\n");
    return 0;
}

/*
[child.c]
#include <stdio.h>
#include <stdlib.h>
#include <dos.h>

int main(int argc,char *argv[])
{
    int delay;
    if(argc<=1)
        exit(EXIT_FAILURE);
    delay=atoi(argv[1]);
    printf("I am a child going to sleep for %d seconds\n",delay);
    sleep(delay);
    printf("I am a child awakening\n");
    exit(123);
    return 0;
}
*/