高手进阶：UNIX系统环境下高级编程一例

#include "err.h"
#include <dirent.h>
int main(int argc, char* argv[])
{
  DIR *dp;
  struct dirent *dirp;

  if(argc != 2)
    err_quit("usage: ls directory_name");

  if((dp = opendir(argv[1])) == NULL)
     err_sys("Can't open %s", argv[1]);
  while((dirp = readdir(dp)) != NULL)
    printf("%s\n", dirp->d_name);

  close(dp);
  return 0;
}

#include <stdio.h>
void err_quit(const char *fmt)
{
  printf( "%s\n", fmt);
  
}

void err_sys(const char *f, const char *s)
{
  printf("%s %s\n", f, s);
}

[root@localhost apue]# ./a.out .
.
..
apue
apue.h
rk1.c~
err.h
a.out
fig1.3.c
rk1.c