"Segmentation fault (core dumped)" error

[FComegys@aol.com]

I am a software engineer with decades of experience writing C in Vax, Dos & 
Windows environments. This is my first experience with gcc on Unix (actually 
Linux).

I have written a program to be run as a CGI script which returns a Web page 
with a list of filenames (or HTML titles). The program is Ansi-C compliant 
except for reading directories and case insensitive string compare functions 
which are compiler dependent. It was originally developed using MS VC++ 
(please try not to gag). I am testing it on a Red Hat Linux Web server via 
Telnet.

gcc -v returns "gcc version 2.7.2.3 I386-Red Hat-Linux"

My problem involves a "Segmentation fault (core dumped)" error. I  have no 
idea of what this error message is trying to tell me. I located a gcc  
compiler from
Cygwin.com in order to get documentation on the compiler. The man and
textinfo utilities say I need a later version of Windows to run them. 

The "Segmentation fault (core dumped)" error always occurs in the same 
function but at different points. I am certain that it is not caused by a 
random store (bad pointer).
In fact the LESS the function is asked to do, the EARLIER the error occurs. 
That is:

void myfunc(char *fspec, int sorting, int subdirs, other args)
{
 /* code to allocate the array of path names and add current dir as the first 
entry */
  if ( subdirs) 
  {
       GetDirPaths(); /* recursively adds path strings for all subdirs to a 
heap array */
       if (sorting)
       { 
           /* code to sort the pointers to the path strings */
       }
  }
  for (i=0; i < numberofpaths; i++)
  {
     /* code to list files that match fspec and free path string to this dir 
*/
  }
}

When subdirs==0 the error occurs entering the for loop but when subdirs==1 
the error occurs exiting the for loop. When I link in my remaining portion of 
my program, the error occurs returning from the last recursive call to 
GetDirPaths(). When I modified GetDirPaths not to recursively call itself but 
return the number of unread dirs found the error occured calling myfunc! HELP!

I am pretty certain that this error is not caused by faulty program logic at 
the source level. My guess is that it is related to compile/link options that 
 may be necessary for i386 machines, expanding heap size or pointer size, or  
stack size or some other
such reason. 

I build the program with:

 gcc -o myprog.cgi myprog.c    with default CCFLAGS or CCFLAGS=

An explanation of what a "Segmentation fault (core dumped)" error actually
is or any hint as what compilier/link options to use or any other push in the
right direction would be greatly appreciated.

Thank you in advance for your assistance,

Frank Comegys
fcomegys@aol.com

ps. I know that I can read both the dirs and files in one pass using gcc and 
intend to  do so after I develop a fnmatch function for MSVC++ which 
currently requires me to
findfirst(*.*, other args) and check if dir then findfirst(fspec, other args) 
to find targeted files. 

Frank Comegys
fcomegys@aol.com