I just translated a Fortran program to C. The C program consists of a main program and several functions. There is one structure that contains integers, integer arrays, character types, and character arrays that I pass with each call to each function. The main program calls one function which calls another function and depending on specific conditions being satisfied this function calls different functions. Well the problem I am experiencing is that a particular function gets called several hundreds of times. This functions purpose is to read a line using fgets from a file and then using sscanf get the required strings from each line. After several hundred iterations of calling this function the program aborts with a stack overflow. In the debugger, I looked at all of the elements contained in the structure including the arrays and they all looked good. Can anyone tell me what might be happening? If needed I will post my code or part of it. I would have done it but it's length is about 2K lines. Please respond.