UNIX环境高级编程——标准IO-实现查看所有用户

#include <string.h>

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

int main(int argc, char *argv[])

{

	char szBuf[512];

	char szName[512];

	FILE *f = fopen("/etc/passwd","r");

	memset(szBuf, 0, sizeof(szBuf));

	int i;

	while(fgets(szBuf, sizeof(szBuf),f) != NULL)

	{

		memset(szName, 0, sizeof(szName));

		for(i = 0; i< sizeof(szBuf); i++)

		{

			if(':' == szBuf[i])

			{

		   	   	break;

			}

			szName[i] = szBuf[i];

		}

		printf("%s \n", szName);

		memset(szBuf, 0, sizeof(szBuf));

	}

	fclose(f);

}

运行结果：

huangcheng@ubuntu:~$ ./a.out

root

daemon

bin

sys

sync

games

man

lp

mail

news

uucp

proxy

www-data

backup

list

irc

gnats

nobody

libuuid

syslog

messagebus

avahi-autoipd

avahi

couchdb

speech-dispatcher

usbmux

haldaemon

kernoops

pulse

rtkit

saned

hplip

gdm

huangcheng

tftp

statd

sshd

samba

ftp