Re: Problem Debugging C Program

John Hanley said:

<500+ lines of source code>

That's better.

Okay, you seem to have mixed up argc and argv somewhat, although the
effect is only to make the program harder to read, not actually wrong.

In the fprintf in main, replace infile with argc[1] (which we would
normally call argv[1], by the way!).

You shouldn't be passing argc[1] to fopen without first checking that
argv is at least 2.

fopen can fail, returning NULL - check for this.
fgets can fail, returning NULL - check for this.

Any one of these could have caused a segfault. If they don't, I'm sure
there's plenty more scope.

--
Richard Heathfield <http://www.cpax.org.uk>
Email: -www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999
.

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