shell-ip-address(3)

Library Functions Manual

shell-ip-address(3)

NAME

ipv4_ip_subnet, ipv4_mask2prefix, ipv4_prefix2mask, valid_ipv4 - functions to validate the IPv4 address

•ipv4_ip_subnet ipaddr subnet

•ipv4_mask2prefix value

•ipv4_prefix2mask value

•valid_ipv4 ipaddr

Function checks that IP address is in subnet.

Example:

ipv4_ip_subnet 172.16.1.2 172.16.1.0/24; echo res=$?
res=0
ipv4_ip_subnet 172.16.3.2 172.16.1.0/24; echo res=$?
res=1

Function counts the leading 1 bits in the routing mask.

Example:

ipv4_mask2prefix 255.255.0.0
16
ipv4_prefix2mask 255.255.255.0
24

Function converts routing prefix to netmask.

Example:

ipv4_prefix2mask 16
255.255.0.0
ipv4_prefix2mask 24
255.255.255.0

Function checks that given option value is a valid IPv4 address.

regex_byte - Regexp for single octet in an IPv4 address.

regex_ipaddr - Regexp for 4-byte address.

regex_ipv4 - Regexp for IPv4 address (see <http://en.wikipedia.org/wiki/IP_address>). Some first-octet values have special meanings:

•First octet 127 represents the local computer, regardless of what network it is really in. This is useful when testing internal operations.

•First octet 224 and above are reserved for special purposes such as multicasting.

Octets 0 and 255 are not acceptable values in some situations, but 0 can be used as the second and/or third octet (e.g. 10.2.0.100).

Authors and contributors of the programs included in the libshell package are listed in the COPYING file.

Report bugs to the authors.

2024-02-08