linux C程序中执行和终止一个可执行程序

执行和终止一个可执行程序可用execvp():

执行：
char *arg[]= {"snmpd", "-c  snmpd.conf"};
execvp(arg[0], arg[]);

终止killall：

if (find_pid_by_name("dnsmasq") < 0)
  return ret;
char *arg[]= {"killall", "-9", "snmpd"};
 
execvp(arg[0], arg[]);

find_pid_by_name()实现如下：
/* from busybox find_pid_by_name.c */
int  find_pid_by_name( char* pidName)
{
    DIR *dir;
    struct dirent *next;
    pid_t* pidList=NULL;
    int i=0;

    dir = opendir("/proc");

    while ((next = readdir(dir)) != NULL) {
        FILE *status;
        char filename[READ_BUF_SIZE];
        char buffer[READ_BUF_SIZE];
        char name[READ_BUF_SIZE];

        /* Must skip ".." since that is outside /proc */
        if (strcmp(next->d_name, "..") == 0)
            continue;

        /* If it isn't a number, we don't want it */
        if (!isdigit(*next->d_name))
            continue;

        sprintf(filename, "/proc/%s/status", next->d_name);
        if (! (status = fopen(filename, "r")) ) {
            continue;
        }
        if (fgets(buffer, READ_BUF_SIZE-1, status) == NULL) {
            fclose(status);
            continue;
        }
        fclose(status);

        /* Buffer should contain a string like "Name:   binary_name" */
        sscanf(buffer, "%*s %s", name);
 //printf("buffer=[%s] name=[%s]/n",buffer,name);
        if (strcmp(name, pidName) == 0) {
 /*
            pidList=realloc( pidList, sizeof(pid_t) * (i+2));
            pidList[i++]=strtol(next->d_name, NULL, 0);
 */
  closedir(dir);
  return 0;
 }
    }

    if (dir)
  closedir(dir);
    return -1;
}