perror - bash implementation

perror

#!/bin/bash

errno_headers="/usr/include/asm-generic/errno-base.h /usr/include/asm-generic/errno.h"


print_usage () {
    echo "Usage: ${0##*/} ERRNO"
}

case $1 in
    [1-9]|[1-9][0-9]|[1-9][0-9][0-9])
    grep --no-filename "\<$1\>" $errno_headers
        ;;
    (-h|--help)
        print_usage
        exit 1
        ;;
    (*)
        print_usage
        exit 1
        ;;
esac