freebsd-skq/lib/libopenbsd/getdtablecount.c
rodrigc 9a0b9f3b8c Implemtn getdtablecount() to count open file descriptors for current process.
Use underlying sysctl implemented by mjg in r290473.

PR:                    194985
Reviewed by:           bapt, mjg
Differential Revision: https://reviews.freebsd.org/D4084
2015-11-14 23:07:38 +00:00

59 lines
1.8 KiB
C

/*-
* Copyright (c) 2015 Craig Rodrigues
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/sysctl.h>
#include <stddef.h>
int getdtablecount(void);
/*
* Return the count of open file descriptors for this process.
*
*/
int
getdtablecount(void)
{
int mib[4];
int error;
int nfds;
size_t len;
len = sizeof(nfds);
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_NFDS;
mib[3] = 0;
error = sysctl(mib, 4, &nfds, &len, NULL, 0);
if (error)
return (-1);
return (nfds);
}