[squid-users] Hi Help Required in creating custom authenticator

Hi
i am creating the custom authenticator for squid where there is a quota option.

i am using the following logic.
1. authenticate with any another exe(authenticators available for
squid) using the squid logic, if username and password is ok then
output is ok, everything else error.
2. username and quota is in one txt file, read those and store in an
array @ the startup of the application.
3. if ok from other exe then check the quota, if its less than or
equal to then send ok to squid, or else send err.
4. retrive user's accessed size using logfiles with the use of size attribute.

now i will come to the help i required.
i am not a advance programmer in c.
i am learining c still.
i need a logic or if possible code where i can send input to other exe
and get the output.
validate the output and print it.
and then i can proceed with my logic.
any suggestions are welcome please.

-- 
Best regards,
Mahesh.G