C语言fgetpwent()函数：读取密码格式
相关函数：fgetgrent
头文件：#include <pwd.h> #include <stdio.h> #include <sys/types.h>
定义函数：struct passwd * fgetpwent(FILE * stream);
函数说明：fgetpwent()会从参数stream 指定的文件读取一行数据, 然后以passwd 结构将该数据返回. 参数stream 所指定的文件必须和/etc/passwd 相同的格式. passwd 结构定义请参考getpwent().
返回值：返回 passwd 结构数据, 如果返回NULL 则表示已无数据, 或有错误发生.
范例
#include <pwd.h>
#include <sys/types.h>
main()
{
struct passwd *user;
FILE *stream;
stream = fopen("/etc/passwd", "r");
while((user = fgetpwent(stream)) != 0)
{
printf("%s:%d:%d:%s:%s:%s\n", user->pw_name, user->pw_uid, user->pw_gid,
user->pw_gecos, user->pw_dir, user->pw_shell);
}
}
执行：
root:0:0:root:/root:/bin/bash
bin:1:1:bin:/bin:
daemon:2:2:daemon:/sbin:
adm:3:4:adm:/var/adm:
lp:4:7:lp:/var/spool/lpd:
sync:5:0:sync:/sbin:/bin/sync
shutdown:6:0:shutdown:/sbin:/sbin/shutdown
halt:7:0:halt:/sbin:/sbin/halt
mail:8:12:mail:/var/spool/mail:
news:9:13:news:var/spool/news
uucp:10:14:uucp:/var/spool/uucp:
operator:11:0:operator :/root:
games:12:100:games:/usr/games:
gopher:13:30:gopher:/usr/lib/gopher-data:
ftp:14:50:FTP User:/home/ftp:
nobody:99:99:Nobody:/:
xfs:100:101:X Font Server: /etc/Xll/fs:/bin/false
gdm:42:42:/home/gdm:/bin/bash
kids:500:500: : /home/kids:/bin/bash
头文件：#include <pwd.h> #include <stdio.h> #include <sys/types.h>
定义函数：struct passwd * fgetpwent(FILE * stream);
函数说明：fgetpwent()会从参数stream 指定的文件读取一行数据, 然后以passwd 结构将该数据返回. 参数stream 所指定的文件必须和/etc/passwd 相同的格式. passwd 结构定义请参考getpwent().
返回值：返回 passwd 结构数据, 如果返回NULL 则表示已无数据, 或有错误发生.
范例
#include <pwd.h>
#include <sys/types.h>
main()
{
struct passwd *user;
FILE *stream;
stream = fopen("/etc/passwd", "r");
while((user = fgetpwent(stream)) != 0)
{
printf("%s:%d:%d:%s:%s:%s\n", user->pw_name, user->pw_uid, user->pw_gid,
user->pw_gecos, user->pw_dir, user->pw_shell);
}
}
执行：
root:0:0:root:/root:/bin/bash
bin:1:1:bin:/bin:
daemon:2:2:daemon:/sbin:
adm:3:4:adm:/var/adm:
lp:4:7:lp:/var/spool/lpd:
sync:5:0:sync:/sbin:/bin/sync
shutdown:6:0:shutdown:/sbin:/sbin/shutdown
halt:7:0:halt:/sbin:/sbin/halt
mail:8:12:mail:/var/spool/mail:
news:9:13:news:var/spool/news
uucp:10:14:uucp:/var/spool/uucp:
operator:11:0:operator :/root:
games:12:100:games:/usr/games:
gopher:13:30:gopher:/usr/lib/gopher-data:
ftp:14:50:FTP User:/home/ftp:
nobody:99:99:Nobody:/:
xfs:100:101:X Font Server: /etc/Xll/fs:/bin/false
gdm:42:42:/home/gdm:/bin/bash
kids:500:500: : /home/kids:/bin/bash
