writing a mkdir -p C program

wch705 · 04-09-2011, 07:36 PM

i am learning how to write a mkdir with -p option.
I am struggling for creating subfolders.
the chdir() is not working and thus subdirectories can't be created.
could someone please have a look for me,thanks?

Code:

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <dirent.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <string.h>

void tokenizer(char *path);
main(int ac,char *av[])
{
	
	int result;
	if (strcmp(av[1],"-p")!=0)
	{
		if (mkdir(av[2],0644)==-1)
		{
			perror("cant make it");
			exit(1);
		}
	
	}
	else if (strcmp(av[1],"-p")==0)
	tokenizer(av[2]);
	
	return EXIT_SUCCESS;
}
void tokenizer(char *path)
{
	char *dir;
	if (mkdir(path, 0644)==-1)
	{
		dir=strtok(path,"/");
		while (dir!=NULL)
		{
			printf("%s\n",dir);
			mkdir(dir, 0644);
			if (chdir(dir)==-1)
			printf("not right\n");
			dir=strtok(NULL,"/");

		}
	
	}
}

dwhitney67 · 04-09-2011, 10:20 PM

I would suggest that you avoid the usage of chdir(); that sort of violates what I believe the command-line mkdir is doing. Consider the following -- if you want to make the series of directories tmp/foo/morefoo, then you would first create tmp, then tmp/foo, and finally tmp/foo/morefoo. Check for errors along the way; abort if any are produced. You may also want to consider employing the use of stat() or lstat() to see if the directory exists prior to doing anything.

Btw, you need to set the execute-bit on the directories you create. 0644 is not appropriate; try 0755, or something more or less restrictive. In fact, allow the user to specify the mode, using a -m option, similar to the real mkdir.

Good luck with your homework!