IPv4, IPv6, inet_ntoa(), inet_aton(), inet_pton(), inet_ntop():Hexadecimal to Decimal

I need to write a C program to convert an IP address, in IPv6 format, (that is in hexadecimal)
to the standard IP address format (that is 255.255.255.255).

Example:
a1b2:c3d4 after conversion : 161.178.195.212

I found a way to do that using the strtol() function but I know there are functions that can manipulate IPv4 or IPv6 addresses
such as inet_ntoa(), inet_aton(), inet_pton(), inet_ntop()

I would like to know if there is a way to make such conversion using one of these functions.

any idea ?

thanks for your help

thanks for the valuable info but the use of gethostbyaddr() to get the IP address is out of question , since it is sort of hard coded :

char * IPv4_address; /* IPv4 address i.e. a1b2:c3d4 */

And now all I need to do is convert a1b2:c3d4 to 161.178.195.212