ULIMIT and 'too many open files

[DGRFL]

Hello,

My communication server process tells me it can't open more files. Here is some more information.

System definitions : (were checked with ulimit command)
- Soft limit 1024
- Hard limit 4096

My program tries to open 260 files (argument passed on command line)

#include <stdio.h>
#include <errno.h>
#include <sys/resource.h>


int main(int argc, char *argv[])
{
int i;
int count;
FILE *aFiles[6000];
long lValue;
lValue = sysconf (_SC_OPEN_MAX);
printf(&quot;Sysconf returns %ld\n&quot;,lValue);

count = atoi(argv[1]);
for (i=0; i< count + 5; i++)
{
aFiles = fopen(&quot;files.c&quot;,&quot;r&quot;
if (aFiles == NULL)
printf(&quot;Error opening file %d %d \n&quot;,i,errno);
}
}

The sysconf tool tells me 1024, but starting from file 253 I receive EMFILES return codes.

Somebody at Sun Support told me to adapt the OPEN_MAX line in the limits.h header file, but this include file is not included in my project, and I cannot believe this is a good solution.

Does anybody have any suggestions ?


Regards,

Luc

 

[DGRFL]

Hello,

Here is some more information. It seems that the FILE * structure as defined by Solaris 8 only allows for 255 files to be opened (they use 8 bits of memory)

This means that when a process is using more files, functions like fprintf() fopen, fseek() etc can no longer be used !!!!

Is this true, is there a workaround : if not, I need to revise the application I am working at thoroughly.

Regards,

Luc