Just a quick appendum. Be careful to make a copy of @_ locally if you are manipulating things a bit, eg:
#!/usr/bin/perl -w
use strict;
my @words = ('These','are','words',"\n");
print "Original: @words";
safesub(@words);
print "After safe sub: @words";
unsafesub(@words);
print "After unsafe sub: @words";
exit(0);
sub safesub {
print "safesub to uppercase: ";
my @uppercasewords = @_;
for (@uppercasewords) {
tr/a-z/A-Z/;
}
print "@uppercasewords";
}
sub unsafesub {
print "unsafesub to uppercase: ";
for (@_) {
tr/a-z/A-Z/;
}
print "@_";
}
# output
Original: These are words
safesub to uppercase: THESE ARE WORDS
After safe sub: These are words
unsafesub to uppercase: THESE ARE WORDS
After unsafe sub: THESE ARE WORDS
Notice how after unsafe sub has been called that @words has changed. If that's not what you're expecting, it can sometimes give you a shock. So unless the sub is very trivial, or you specifically do intend to amend the caller var(s), make sure you make a copy to play with in the sub.
.02
cLive ;-)
--
seek(JOB,$$LA,0);
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