Thanks for the info. I am using mkstemp() when a shared memory segment is created and with the latest changes in Nemesis I guess only one proc creates the shm segment. Regards, Jayesh -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Anthony Chan Sent: Friday, October 31, 2008 2:38 PM To: [email protected] Subject: Re: [mpich2-core] Implicit decl warning with "-ansi"+"-Wall" option BTW, make sure you are not calling mkstemp() in every MPI process. mkstemp() opens a file to check if the temporary file is unique. Imagine what will happen if a 32K-process job calls mkstemp() by every process on a common file system.... MPE got bitten by this once when it was first tested on BGW, it crashed/hung GPFS... ----- "Anthony Chan" <[email protected]> wrote:

The gcc compiler options swallow the mkstemp declaration. MPICH2 or MPE's configure checks for mkstemp declaration (and other common libc functions) to see if it exists (especially when --enables-strict is used) If not, the configure will insert mkstemp declaration.

----- "Jayesh Krishna" <[email protected]> wrote:

...

Hi,

========================================= #include <stdlib.h>

/* extern int mkstemp(char *); */ int main(int argc, char *argv[]){ int fd = -1; char template[] = "temp_XXXXXX"; fd = mkstemp(template); return 0; } =========================================

The code above gives me the following warning when compiled with "-Wall" & "-ansi" option with gcc,

========================================= shakey:/sandbox/jayesh/Enhancements/NemesisOnWindows/testPgms> gcc -ansi -Wall test.c test.c: In function �?~main�?T: test.c:7: warning: implicit declaration of function �?~mkstemp�?T =========================================

Any ideas ?

-Jayesh