Unix programming in C

elilaw — Thu, 28 Sep 2006 18:39:39 +0800

Hi, this is my 1st time posting in Lowyat. I have quite alot of difficulty in trying to get this code to produce the list of directories & files out on the Unix terminal.

Ok, this is actually Unix Programming with C.... The code should be emulating what the "find" command does.

eg ...
find -print {in current directory}
./hello.c
./world.c
./hello.exe

Now i'm having difficulty trying to get my code doing that... except my code should list the current directory's files & directories (including . and ..) in the terminal:
$hello.c
$world.c
$hello.exe

Pls note: I should also use the "getopt" command call in the code, but I don't know how to.

okie, this is my code at the moment:

CODE

#include <stdio.h> /* for printf */
#include <stdlib.h> /* for exit */
#include <getopt.h>
#include <dirent.h>
#include <sys/types.h>

int
main (int argc, char **argv) {
int c;
int digit_optind = 0;

while (1) {
int this_option_optind = optind ? optind : 1;
int option_index = 0;
/* You'll need to read the manual to figure out what all the
* arguments are!
*/
static struct option long_options[] = {
{"cnewer", 1, 0, 0},
{"cmin", 1, 0, 0},
{"ctime", 1, 0, 0},
{"help", 0, 0, 0},
{0, 0, 0, 0}
};

#define OPT_NEWER 0
#define OPT_CMIN 1
#define OPT_CTIME 2
#define OPT_HELP 3

c = getopt_long_only (argc, argv, "", long_options, &option_index);

if (c == -1)
printf("c = -1 & that's why we're killing it\n");
//do_ls();
break;

switch (c) {
case 0:
printf ("option %s", long_options[option_index].name);
if (optarg)
printf (" with arg %s", optarg);
printf ("\n");
if (option_index == OPT_HELP) usage();
break;

case '?':
break;

default:
printf ("?? getopt returned character code 0%o ??\n", c);
}
}

if (optind < argc) {
printf ("non-option ARGV-elements: ");
while (optind < argc)
printf ("%s ", argv[optind++]);
printf ("\n");
}

exit (0);
}
usage() {
printf("Usage: myfind [pathname] [args]\n");
printf(" pathname should probably be a directory\n");
printf(" args are any of the following (anded together):\n");
printf(" -print, -cmin, -ctime, -cnewer, -gid, -group \n");
printf(" -uid, -user, -empty, -links, -name\n");
printf("For details see find(1)\n");
}

void do_ls (char dirname[]) {

DIR *dir_ptr;
struct dirent *direntp;

if ( (dir_ptr = opendir(dirname)) == NULL)
fprintf(stderr,"ls1: cannot open %s\n", dirname);

else
{
while ((direntp = readdir(dir_ptr)) != NULL)
printf("%s\n", direntp->d_name);
closedir(dir_ptr);
}
}

Can anyone pls help me?? I'm struggling with programming as itself already... It's just wayyyy too hard Stupid me for taking this in uni....

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Unix programming in C