Liunx实验八(2)---系统文件目录操作实验

步骤1：同上一节

步骤2：建立目录

　　cd workdir/linux/application/8-io

　　mkdir -p dir/example

　　cd dir/example

　　touch 1.c 2.c 　　　　　　创建两个文件

　　cd ../　　　　　　　　　　返回上一级

步骤3：复制

　　cp /mnt/hgfs/share/2.Linux系统实验部分\07.Linux系统文件目录操作编程实验/实验代码/7.2/myls.c 8-io/dir/

步骤4：执行

　　gcc myls.c -o myls

　　./myls example

附：程序源码

  1 #include <stdio.h>
  2 #include <stdlib.h>
  3 #include <sys/types.h>
  4 #include <sys/stat.h>
  5 #include <errno.h>
  6 #include <unistd.h>
  7 #include <string.h>
  8 #include <time.h>
  9 #include <pwd.h>
 10 #include <grp.h>
 11 #include <dirent.h>
 12 
 13 #define N 128
 14 
 15 int aflag = 0, lflag = 0;
 16 
 17 void displayfile(char *name, char *showname);
 18 void displaydir(const char *name);
 19 
 20 int main(int argc, char *argv[])
 21 {
 22     struct stat buf;
 23     int ch, i;
 24 
 25     if (argc < 2)
 26     {
 27         fprintf(stdout, "usage: %s filename\n", argv[0]);
 28         exit(-1);
 29     }
 30 
 31     while ((ch = getopt(argc, argv, "al")) != -1)
 32     {
 33         switch(ch)
 34         {
 35             case 'a': aflag = 1; break;
 36             case 'l': lflag = 1; break;
 37             default:
 38                       printf("wrong option %c\n", optopt);
 39         }
 40     }
 41 
 42 //    printf("aflag=%d lflag=%d\n", aflag, lflag);
 43 
 44     for (i = optind; i < argc; i++)
 45     {
 46         if (stat(argv[i], &buf) == -1)
 47         {
 48             perror("stat");
 49             exit(-1);
 50         }
 51 
 52         if (!S_ISDIR(buf.st_mode))
 53             displayfile(argv[i], argv[i]);
 54         else
 55             displaydir(argv[i]);
 56     }
 57     if (lflag == 0)
 58         printf("\n");
 59     return 0;
 60 }
 61 
 62 void displayfile(char *name, char *showname)
 63 {
 64     struct stat buf;
 65     struct tm *p;
 66     int i = 8;
 67 
 68     if (lflag == 0)
 69     {
 70         printf("%s ", showname);
 71         return;
 72     }
 73 
 74     if (stat(name, &buf) == -1)
 75     {
 76         perror("stat");
 77         exit(-1);
 78     }
 79 
 80     switch (buf.st_mode & S_IFMT)
 81     {
 82     case S_IFSOCK: printf("s"); break;
 83     case S_IFLNK:  printf("l"); break;
 84     case S_IFREG:  printf("-"); break;
 85     case S_IFBLK:  printf("b"); break;
 86     case S_IFDIR:  printf("d"); break;
 87     case S_IFCHR:  printf("c"); break;
 88     case S_IFIFO:  printf("p"); break;
 89     default:
 90                    printf("?");
 91     }
 92 
 93     while (i >= 0)
 94     {
 95         if ((buf.st_mode) >> i & 1)
 96         {
 97             switch (i % 3)
 98             {
 99                 case 2: printf("r"); break;
100                 case 1: printf("w"); break;
101                 case 0: printf("x"); break;
102             }
103         }
104         else
105         {
106             printf("-");
107         }
108         i--;
109     }
110 
111     printf(" ");
112 
113     /* hard links */
114     printf("%d", buf.st_nlink);
115 
116     /* uid gid */
117     printf(" %s %s  ", getpwuid(buf.st_uid)->pw_name, getgrgid(buf.st_gid)->gr_name);
118 
119     printf("%ld  ", buf.st_size);
120 
121     p = localtime(&buf.st_mtime);
122     printf("%d-%d-%d %d:%d    ", p->tm_year+1900, p->tm_mon+1, 
123                     p->tm_mday, p->tm_hour, p->tm_min);
124     printf("%s\n", showname);
125 }
126 
127 void displaydir(const char *name)
128 {
129     DIR *dir;
130     struct dirent *diritem;
131     char str[N];
132 
133     dir = opendir(name);
134     while ((diritem = readdir(dir)) != NULL)
135     {
136         if (strncmp(".", diritem->d_name, 1) == 0 && aflag == 0)
137             continue;
138         sprintf(str, "./%s", diritem->d_name);
139         displayfile(str, diritem->d_name);
140     }
141 }