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Old 11-14-2007
karthikb23 karthikb23 is offline
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Join Date: Nov 2007
Posts: 18
Wierd C program. Help Needed

Hi,
Please see this:
When i make a declaration as:

char *i, j[15], *k;
and then do
sprintf( k, "print.sh %s", i );

the program works fine.

But when i change the declaration to:
char *i, *k;
and then do
sprintf( k, "print.sh %s", i );
I get a segmentation fault at the 'sprintf' statement.

The program works only when j is an array of 15. Nothing less/more

Please Note: variable j is just a dummy. I do absolutely nothing with it.
Also, i know using sprintf the way i have done is illegal. The pointer is not assigned to anything, prior to such a statement.

It may be silly but could someone please explain why this happens? Guess something to do with the way memory is allocated.

Thanks in advance!