Function and stuff

Hi all,

I have been writing a function which opens a file and return the handling for future use… I’m missing something there… can you please help?

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>


FILE* openFile (char* text, char* handleName);
		
void main ()
{	
	openFile ("enter filename: ", "myHandleName");

}

FILE* openFile (char* text, char* handleName)
{
	char fileName[25];
	printf ("%s", text);
	scanf ("%s",fileName);
	handleName=fopen (fileName,"rt"); //opening second file for reading.
	if (handleName==NULL)
	{
		printf ("\nCannot open second file: %s\n",fileName);
		exit(0);
	}
	return (handleName);
}

>void main ()
The correct definition of main is:

Code:

int main ( void )
{
  return 0;
}

>openFile ("enter filename: ", "myHandleName");
I'm thinking you want something more like this:

Code:

FILE *myHandleName = openFile("enter filename: ");

>scanf ("%s",fileName);
What if the name has spaces? fgets would be better here

>handleName=fopen (fileName,"rt");
fopen returns a FILE*, not a char*. Also, t is not a standard mode specifier for fopen.

>exit(0);
Do you really want to terminate the program just because a file can't be opened? What if the calling code can recover? If this function is meant to be generic, the last thing a library function should do is close the program. In fact, a good library function should refrain from taking user input (so that it can be used non-interactively) or logging errors (which is the job of the calling code). Really the best you can do is return a null pointer on error, which is basically what fopen does. So such a function would be a pointless wrapper in the first place.

Thanks, Prelude for your reply, but I'm not sure you have understand me (or maybe I'm looking for something which is impossible)...
In the main section, I would like (in 1 line) to call a function which will ask from the user the filename he wants to open and return the handle of this action so that it will be usable in the main section. I don't want to have scanf's in the main. I want a "clean" main

Is it possible at all to specify (by calling the function) the handle name I would like to use?

Thanks, again...

In C, the handle is represented as a FILE *. char * are not file handles.

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

FILE* openFile (char* text, char* handleName);
		
void main ()
{
	FILE * myHandle;
	myHandle = openFile ("enter filename: ");

}

FILE* openFile (char* text)
{
	FILE * handle;
	char fileName[25];
	printf ("%s", text);
	scanf ("%s",fileName);
	handle=fopen (fileName,"rt"); //opening second file for reading.
	if (handle==NULL)
	{
		printf ("\nCannot open second file: %s\n",fileName);
		exit(0);
	}
	return (handle);
}

> void main ()
OMG OMG - 500 posts and still void main'ing

Doomed I tell you, we're all DOOMed.

Thanks, QuestionC and Thanks, Salem! I promise I'll not void main again!