412f3e8aa4
Stops the compilier (correctly) complaining: lib/test_shm.c: In function ‘main’: lib/test_shm.c:65:23: warning: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 2 has type ‘int’ [-Wformat=] 65 | printf("SHMID: %llx\n", shm_id); | ~~~^ ~~~~~~ | | | | | int | long long unsigned int shm_id is an int which is what shmget() returns. Strangely pmap has always scanned this in as a llx even though the maps "inode" column is the same number that shmget() returns. Signed-off-by: Craig Small <csmall@dropbear.xyz>
70 lines
2.0 KiB
C
70 lines
2.0 KiB
C
/*
|
|
* test_shm -- program to create a shared memory segment for testing
|
|
*
|
|
* Copyright 2022 Craig Small <csmall@dropbear.xyz>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*/
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <sys/shm.h>
|
|
#include "c.h"
|
|
|
|
#define DEFAULT_SLEEPTIME 300
|
|
#define SHM_SIZE 50
|
|
|
|
static void usage(void)
|
|
{
|
|
fprintf(stderr, " %s [options]\n", program_invocation_short_name);
|
|
fprintf(stderr, " -s <seconds>\n");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
int main(int argc, char *argv[])
|
|
{
|
|
int sleep_time, opt;
|
|
int shm_id;
|
|
void *shm_addr;
|
|
|
|
sleep_time = DEFAULT_SLEEPTIME;
|
|
while ((opt = getopt(argc, argv, "s:")) != -1)
|
|
{
|
|
switch(opt)
|
|
{
|
|
case 's':
|
|
sleep_time = atoi(optarg);
|
|
if (sleep_time < 1)
|
|
{
|
|
fprintf(stderr, "sleep time must be 1 second or more\n");
|
|
usage();
|
|
}
|
|
break;
|
|
default:
|
|
usage();
|
|
}
|
|
}
|
|
|
|
/* get some shared memory */
|
|
if ( (shm_id = shmget(IPC_PRIVATE, SHM_SIZE, IPC_CREAT | 0666)) < 0)
|
|
xerr(EXIT_FAILURE, "Unable to shmget()");
|
|
if ( (shm_addr = shmat(shm_id, NULL, SHM_RDONLY)) < 0)
|
|
xerr(EXIT_FAILURE, "Unable to shmat()");
|
|
printf("SHMID: %x\n", shm_id);
|
|
sleep(sleep_time);
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|