2 * Copyright (c) 2016, Marie Helene Kvello-Aune
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36 #include <sys/ioctl.h>
43 int main(int argc, char *argv[])
46 errx(EINVAL, "Invalid number of arguments."
47 " First argument should be interface name, second argument"
48 " should be the MTU to set.");
54 /* We have a static number of arguments. Therefore we can do it simple. */
55 ifname = strdup(argv[1]);
56 mtu = (int)strtol(argv[2], &ptr, 10);
58 printf("Interface name: %s\n", ifname);
59 printf("New MTU: %d", mtu);
61 libifc_handle_t *lifh = libifc_open();
62 if (libifc_set_mtu(lifh, ifname, mtu) == 0) {
63 printf("Successfully changed MTU of %s to %d\n", ifname, mtu);
69 switch (libifc_err_errtype(lifh)) {
71 warnx("couldn't create socket. This shouldn't happen.\n");
74 if (libifc_err_ioctlreq(lifh) == SIOCSIFMTU) {
75 warnx("Failed to set MTU (SIOCSIFMTU)\n");
78 "Failed to set MTU due to error in unexpected ioctl() call %lu. Error code: %i.\n",
79 libifc_err_ioctlreq(lifh),
80 libifc_err_errno(lifh));
85 "Should basically never end up here in this example.\n");