p5-15.c

来自「UNIX程序设计教程」· C语言 代码 · 共 42 行

#include <grp.h>
#include <pwd.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
int main(void)
{
    uid_t me;
    struct passwd  *my_passwd;
    struct group   *my_group;
    char           **members;
    me = getuid();              /* 获得用户ID （§6.11）*/
    my_passwd = getpwuid(me);   /* 获得用户信息 */
    if (!my_passwd) {
        printf ("Couldn't find out about user %d.\n", (int) me);
        exit(EXIT_FAILURE);
    }
    /* 打印用户信息 */
    printf ("I am %s.\n", my_passwd->pw_gecos);
    printf ("My login name is %s.\n", my_passwd->pw_name);
    printf ("My uid is %d.\n", (int) (my_passwd->pw_uid));
    printf ("My home directory is %s.\n", my_passwd->pw_dir);
    printf ("My default shell is %s.\n", my_passwd->pw_shell);
    /* 获得缺省组ID信息 */
    my_group = getgrgid (my_passwd->pw_gid);
    if (!my_group) {
        printf ("Couldn't find out about group %d.\n",
                   (int) my_passwd->pw_gid);
        exit (EXIT_FAILURE);
    }
    /* 打印组信息 */
    printf("My default group is %s (%d).\n",
               my_group->gr_name, (int) (my_passwd->pw_gid));
    printf("The members of this group are:\n");
    members = my_group->gr_mem;
    while(*members){
        printf("  %s\n", *(members));
        members++;
    }
    return EXIT_SUCCESS;
}