OSExperiment/program_task/multi_process/mysys2.c at master · TLMichael/OSExperiment · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>

#define MAX_BUFFLEN	1024
#define MAX_NUM 100

int mysys(const char *cmdstring)
{
	pid_t pid;
    int status = -1;

    if (cmdstring == NULL)
        return 1;

    if ((pid = fork()) < 0)
        status = -1;
    else if (pid == 0)
    {
        execl("/bin/sh", "sh", "-c", cmdstring, (char *)0);
        exit(127);
    }
    else
    {
        while (waitpid(pid, &status, 0) < 0)
        {
            if (errno != EINTR)
            {
               status = -1;
               break;
            }
        }
    }

    return status;
}

int main()
{
	//char *argv[] = {"ls", "/", NULL};
	//execvp("ls", argv);
    int res;
    res = mysys("");
    printf("[Status] %d\n", res);
	res = mysys("pwd");
    printf("[Status] %d\n", res);
    res = mysys("echo ,HELLO  WORLD ,  sdfa sdfadf        ss   ");
    printf("[Status] %d\n", res);
    res = mysys("echo /G");
    printf("[Status] %d\n", res);
    res = mysys("echo ,,");
    printf("[Status] %d\n", res);
    res = mysys("echo");
    printf("[Status] %d\n", res);

    res = mysys("asdfasdf");
    printf("[Status] %d\n", res);


    printf("----------------------------------------------------------\n");
    res = mysys("echo HELLO WORLD");
    printf("[Status] %d\n", res);
    printf("----------------------------------------------------------\n");
    res = mysys("ls /");
    printf("[Status] %d\n", res);
    printf("----------------------------------------------------------\n");

    return 0;
}