Increase stack size in Linux with setrlimit

Normally you would set the stack size early on, e,g, at the start of main(), before calling any other functions. Typically the logic would be:

• call getrlimit to get current stack size
• if current size < required stack size then
  • call setrlimit to increase stack size to required size

In C that might be coded something like this:

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

int main (int argc, char **argv)
{
    const rlim_t kStackSize = 64L * 1024L * 1024L;   // min stack size = 64 Mb
    struct rlimit rl;
    int result;

    result = getrlimit(RLIMIT_STACK, &rl);
    if (result == 0)
    {
        if (rl.rlim_cur < kStackSize)
        {
            rl.rlim_cur = kStackSize;
            result = setrlimit(RLIMIT_STACK, &rl);
            if (result != 0)
            {
                fprintf(stderr, "setrlimit returned result = %d\n", result);
            }
        }
    }

    // ...

    return 0;
}