apue——读目录操作

头文件：

#define _POSIX_C_SOURCE 200809L

#include 
#include 
#include 

#if defined(MACOS) || !defined(TIOCGWINSZ)
#include 
#endif

#include 
#include 
#include 
#include 
#include 
#include 

#define MAXLINE 4096

#define FILE_MODE (S_IRUSE | S_IWUSR | S_IRGRP | S_IROTH)

#define DIR_MODE (FILE_MODE | S_IXUSR | S_IXGRP | S_IXOTH)

#define min(a,b) ((a) < (b) ? (a) : (b))
#define max(a,b) ((a) > (b) ? (a) : (b))

主程序：

#include "apue.h"
#include 

int main( int argc, char* argv[] ) {
    DIR* dp;
    struct dirent* dirp;
    
    if ( argc != 2 ){
        printf("usage: is directory_name");
        exit(1);
        //err_quit("usage: is directory_name");
    }
    if (( dp = opendir(argv[1])) == NULL){
        printf("can't open %s", argv[1]);
        exit(1);
        //err_sys("can't open %s", argv[1]);
    }
    while ((dirp = readdir(dp)) != NULL) {
        printf("%s\n",dirp->d_name);
    }
    closedir(dp);
    exit(0);
}

makefile文件：

edit: ls.o
	gcc -o edit ls.o
ls.o:ls.c apue.h
	gcc -c ls.c
clean:rm ls.o

　终端执行命令：

make edit
./edit /dev

　得到如下结果：

.
..
vcsa6
vcs6
vcsa5
vcs5
vcsa4
vcs4
vcsa3
vcs3
/*........*/等等