Line numbers should not matter for ini files, ini files have different sections each with different entries, the location of a section/entry has no effect on it's meaning (well, it shouldn't)
Therefore I see no reason for implementing a strange alias that is against the very foundation of ini files.
And, what should your $findline(file.ini,entry1) return in this case:
[section1]
entry1=blub
entry2=blah
[section2]
entry1=maybethis
entry2=ploink
[section3]
entry1=yesitcangetworse
As for your problem:
-> use $read with one of the search switches and $readn
-> dump ini files, use a normal text file and use provious option
-> dump ini files, use a normal text file and use /fopen and the other commands/identifiers on that help page to write or read the entire ini file in one go
-> dump ini files and use a hash table, or several tables if needed <- my suggestion
