regular file versus directory

jaepi · 05-11-2007, 01:15 AM

using c++ and asking a user, how would you know if he entered a regular file or a directory...what functions is applicable..

bigearsbilly · 05-11-2007, 02:26 AM

man stat

blah blah blah

ta0kira · 05-11-2007, 11:19 AM

Quote:

Originally Posted by bigearsbilly

blah blah blah

That doesn't sound like C++ to me

C++ doesn't acknowlege the existence of directories, per se, probably because of the extensive number of file systems (some might not even use directories.) That means there is no portable way to check that a file name given is a directory; you must resort to using libc when using Linux. Check out 'info libc' or in Konqueror 'info:libc'.

Some file systems will let you open a directory as a file, so an openability test will not be enough.

I make this check in a program of mine. Here is the function I use:

Code:

#include <string>
#include <sys/stat.h>

bool CheckValidity(const std::string &fFile)
{
	//Returns 'false' if the file is a directory
	//Returns 'true' if the file is NOT a directory (includes non-extant)

	struct stat Properties;
	if (stat(fFile.c_str(), &Properties) < 0) return true;
	return !S_ISDIR(Properties.st_mode);
}

ta0kira

bigearsbilly · 05-14-2007, 02:42 AM

Quote:

Originally Posted by ta0kira

That doesn't sound like C++ to me

no, it's java

jaepi · 05-15-2007, 09:31 PM

the problem with the function is, im using char filename instead of string since im using the system() function, w/c asks for a char*...im concatenating commands using strcat() function which is not also compatible with the string data type...

tuxdev · 05-15-2007, 11:10 PM

That's not a problem (although creating the string object would be somewhat pointless). The std::string class defines a conversion from char *.

clib is portable IMO. stat.h is part of the POSIX standard, and even Windows (which is decidedly not POSIX compliant) supports it with a little #ifdef to rename _stat to stat. C isn't a second-class citizen in my C++ world.

jaepi · 05-15-2007, 11:23 PM

i've figured it out...i used this one...const char *temp = filename.c_str();...thanks guys...

ta0kira · 05-16-2007, 07:14 AM

Or just change the argument of the function to 'const char*' and remove the '.c_str()' from the 'stat' call.
ta0kira