pkg-monitoring-plugins/lib/maxfd.c

27 lines
771 B
C

#include "./maxfd.h"
#include <errno.h>
long mp_open_max (void) {
long maxfd = 0L;
/* Try sysconf(_SC_OPEN_MAX) first, as it can be higher than OPEN_MAX.
* If that fails and the macro isn't defined, we fall back to an educated
* guess. There's no guarantee that our guess is adequate and the program
* will die with SIGSEGV if it isn't and the upper boundary is breached. */
#ifdef _SC_OPEN_MAX
errno = 0;
if ((maxfd = sysconf (_SC_OPEN_MAX)) < 0) {
if (errno == 0)
maxfd = DEFAULT_MAXFD; /* it's indeterminate */
else
die (STATE_UNKNOWN, _("sysconf error for _SC_OPEN_MAX\n"));
}
#elif defined(OPEN_MAX)
return OPEN_MAX
#else /* sysconf macro unavailable, so guess (may be wildly inaccurate) */
return DEFAULT_MAXFD;
#endif
return(maxfd);
}