my string array is not working correctly with my filebrowser

[Kazo]

I am trying to copy the string of pent->d_name to an array of strings.

here is the code.

Code: Select all

void ReadDir()
{
	fileCount = 0;

	DIR *pdir;
	struct dirent *pent;
	struct stat statbuf;
	pdir=opendir(currentDir);
	if (pdir)
	{
		while ((pent=readdir(pdir))!=NULL)
		{
			stat(pent->d_name,&statbuf);

	    	if(S_ISDIR(statbuf.st_mode))
			{
				DirList[fileCount] = pent->d_name;
				fileCount++;
			}

	    	if(!(S_ISDIR(statbuf.st_mode)))
			{
				DirList[fileCount] = pent->d_name;
				fileCount++;
			}
		}
		closedir(pdir);
		fileCount--;
	}
	else
	{
		iprintf ("opendir() failure; terminating\n");
	}
}

somehow all the strings in the array are all the same string.

Code: Select all

for(i = 0; i <= fileCount; i++)
	{
		if(i == currentFile)
		{
			currentFilestr = "*";
		}
		else
		{
			currentFilestr = " ";
		}
		iprintf("%s%s\n", currentFilestr, DirList[i]);
	}

[mtheall]

I think you don't understand what this line does:

Code: Select all

DirList[fileCount] = pent->d_name;

This does not copy the contents of one string into another.

[Kazo]

sorry, I am used to C#

I changed it to strcpy(DirList[fileCount], pent->d_name);

and now i get this.

[Discostew]

Sorry to be blunt, but you should probably read up on some of the basics of C. We don't even know what type DirList is, or if it is an array.

[mtheall]

You need to do something like this:

Code: Select all

char * DirList[SIZE];
...
DirList[filecount] = malloc(strlen(pent->d_name)+1);
if(DirList[filecount] != NULL)
  strcpy(DirList[filecount], pent->d_name);
filecount++;

Don't forget to free() all the stuff you malloc'd when you are done with them.

Code: Select all

for(i = 0; i < filecount; i++)
{
  if(DirList[i] != NULL)
  {
    free(DirList[i]);
    DirList[i] = NULL;
  }
}

Also, before you ask more questions about string manipulations and printing them on the DS, you should try these things out in a PC program. And of course, you would try to find the answers to these questions in general C forums, as this is nowhere near DS-specific.

[Kazo]

thanks mtheall.

[WinterMute]

You need to do something like this:

Code: Select all

char * DirList[SIZE];
...
DirList[filecount] = malloc(strlen(pent->d_name)+1);
if(DirList[filecount] != NULL)
  strcpy(DirList[filecount], pent->d_name);
filecount++;

Don't forget to free() all the stuff you malloc'd when you are done with them.

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DirList[filecount] = strdup(pent->d_name);

is much more readable and does the same thing, you'll still need to free the allocated memory when you're finished.

[mtheall]

That works, too. Just make sure you handle the scenario where it can't allocate memory for the string (strdup will return NULL).