I think you want the regex I show in this little program. It starts with an "a", has one of more non-newline characters, then uses the alternation (f|g) to denote that the whole thing can end with either of those characters. 

#!/usr/bin/perl

while( <DATA> )
    {
    chomp;
    print "$_ matches!\n" if /^a.+(f|g)$/;
    }
    
__DATA__
axxxi
bxg
cxxf
axxxh
axxxg
axxxf

[download]
--
brian d foy <bdfoy@cpan.org>

In reply to Re: regular expressions by brian_d_foy
in thread regular expressions by wannabeboy

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