source: bootcd/isolinux/syslinux-6.03/gpxe/src/hci/commands/nvo_cmd.c

#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <getopt.h>
#include <gpxe/settings.h>
#include <gpxe/command.h>

FILE_LICENCE ( GPL2_OR_LATER );

static int show_exec ( int argc, char **argv ) {
        char buf[256];
        int rc;

        if ( argc != 2 ) {
                printf ( "Syntax: %s <identifier>\n", argv[0] );
                return 1;
        }

        if ( ( rc = fetchf_named_setting ( argv[1], buf,
                                           sizeof ( buf ) ) ) < 0 ){
                printf ( "Could not find \"%s\": %s\n",
                         argv[1], strerror ( rc ) );
                return 1;
        }

        printf ( "%s = %s\n", argv[1], buf );
        return 0;
}

static int set_exec ( int argc, char **argv ) {
        int rc;

        if ( argc != 3 ) {
                printf ( "Syntax: %s <identifier> <value>\n", argv[0] );
                return 1;
        }

        if ( ( rc = storef_named_setting ( argv[1], argv[2] ) ) != 0 ) {
                printf ( "Could not set \"%s\"=\"%s\": %s\n",
                         argv[1], argv[2], strerror ( rc ) );
                return 1;
        }

        return 0;
}

static int clear_exec ( int argc, char **argv ) {
        int rc;

        if ( argc != 2 ) {
                printf ( "Syntax: %s <identifier>\n", argv[0] );
                return 1;
        }

        if ( ( rc = delete_named_setting ( argv[1] ) ) != 0 ) {
                printf ( "Could not clear \"%s\": %s\n",
                         argv[1], strerror ( rc ) );
                return 1;
        }
        
        return 0;
}

struct command nvo_commands[] __command = {
        {
                .name = "show",
                .exec = show_exec,
        },
        {
                .name = "set",
                .exec = set_exec,
        },      
        {
                .name = "clear",
                .exec = clear_exec,
        },
};