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33 #include <sys/ioctl.h>
37 #include <libifconfig.h>
41 main(int argc, char *argv[])
45 ifconfig_handle_t *lifh;
48 errx(EINVAL, "Invalid number of arguments."
49 " First argument should be interface name, second argument"
50 " should be the MTU to set.");
53 /* We have a static number of arguments. Therefore we can do it simple. */
54 ifname = strdup(argv[1]);
55 mtu = (int)strtol(argv[2], &ptr, 10);
57 printf("Interface name: %s\n", ifname);
58 printf("New MTU: %d", mtu);
60 lifh = ifconfig_open();
62 errx(ENOMEM, "Failed to open libifconfig handle.");
66 if (ifconfig_set_mtu(lifh, ifname, mtu) == 0) {
67 printf("Successfully changed MTU of %s to %d\n", ifname, mtu);
74 switch (ifconfig_err_errtype(lifh)) {
76 warnx("couldn't create socket. This shouldn't happen.\n");
79 if (ifconfig_err_ioctlreq(lifh) == SIOCSIFMTU) {
80 warnx("Failed to set MTU (SIOCSIFMTU)\n");
83 "Failed to set MTU due to error in unexpected ioctl() call %lu. Error code: %i.\n",
84 ifconfig_err_ioctlreq(lifh),
85 ifconfig_err_errno(lifh));
90 "Should basically never end up here in this example.\n");