TEXT

Return an IPV4 or IPV6 address as a VARCHAR character string.

TEXT(address [,integer])

where address is an IPV4 or IPV6 column, expression, or constant. To specify a constant value for the address, use the IPV4 or IPV6 keyword.

Optionally, you can also specify a second integer argument that represents the subnet mask (in the range of 0 to 32 for IPV4 or 0 to 128 for IPV6).

For example:
premdb=# select hostip, text(hostip) from myhosts;
   hostip    |    text     
-------------+-------------
 10.10.10.5  | 10.10.10.5
 10.10.10.6  | 10.10.10.6
 10.10.10.10 | 10.10.10.10
 10.10.190.1 | 10.10.190.1
(4 rows)

premdb=# select hostip, text(hostip,16) from myhosts;
   hostip    |      text      
-------------+----------------
 10.10.10.5  | 10.10.10.5/16
 10.10.10.6  | 10.10.10.6/16
 10.10.10.10 | 10.10.10.10/16
 10.10.190.1 | 10.10.190.1/16
(4 rows)
premdb=# select text(ipv6 '2001:0db8:85a3:0000:0000:8a2e:0370:0000') from sys.const;
                  text                   
-----------------------------------------
 2001:0db8:85a3:0000:0000:8a2e:0370:0000
(1 row)

premdb=# select text(ipv6 '2001:0db8:85a3:0000:0000:8a2e:0370:0000',128) from sys.const;
                    text                     
---------------------------------------------
 2001:0db8:85a3:0000:0000:8a2e:0370:0000/128
(1 row)