I accidentally used lc where I should have used uc, but you shouldn't get the behaviour you describe either way. 

>type infile
hello h e l l o
bye b y e
bike b i k e

>perl -pe"s/(.)/uc($1)/e" infile > outfile

>type outfile
Hello h e l l o
Bye b y e
Bike b i k e

[download]

or 

>type infile
hello h e l l o
bye b y e
bike b i k e

>type script.pl
while (<>) {
   s/(.)/uc($1)/e;
   print;
}

>perl script.pl infile > outfile

>type outfile
Hello h e l l o
Bye b y e
Bike b i k e

[download]

You must be doing something extra.

In reply to Re^3: Changing the first word to uppercase by ikegami
in thread Changing the first word to uppercase by Anonymous Monk

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