Thread: I need a function that can debug

It's called printf(). You shove them all over your program.

Code:

printf("The program made it to this point.");

Otherwise you can just use a debugger. You might have gotten it with your compiler.

Some useful defines for debugging are:

Code:

__LINE__  /* current line of the source file (<underscore><underscore>LINE<underscore><underscore>) */
__FILE__  /* current source file name */
__TIME__  /* the time this executable was compiled (string) */
__DATE__ /* the date it was compiled (string) */
__func__  /* (C99) name of the current function */

So you could have a debugging macro like this:

Code:

#include <stdio.h>

#define debug_str(s) \
    printf(__FILE__ ":" __func__ "():%i: %s\n", __LINE__, s)

int main(void) {
    debug_str("Before printf()");
    printf("Hello, World!\n");
    debug_str("After printf()");

    return 0;
}

Output:

Code:

debug_str.c:main():7: Before printf()
Hello, World!
debug_str.c:main():9: After printf()

The best debugging tool, however, is a debugger. If you have Dev-C++ or GCC, then you can compile your program with -g and use GDB to debug it:

Code:

C>gcc -g -o hello.exe hello.c

C>gdb hello.exe
This is GDB version x.xx ....
(gdb) run
Hello, World!

The program exited normally.
(gdb) quit
C>

This site has a tutorial on using GDB.