Beefy Boxes and Bandwidth Generously Provided by pair Networks
Keep It Simple, Stupid
 
PerlMonks  

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

Brethren,
In a learning experiment using multiple filehandles in a hash, I stumbled on something that I don't understand.

#/usr/bin/perl -w use strict; local (*E,*F,*G); my $string = <<JUNK; I will print unless I perish JUNK my %rh = (E=> *E, F=> *F, G=> *G); open $rh{$_}, ">test_$_.txt" or die $! for keys %rh; print { $rh{$_}} $_.$string for keys %rh;
# the following (incorrect) line closes the filehandles
close $_ or die $!                        for keys %rh; # so that this (correct) line dies
close $rh{$_} or die $! for keys %rh; #error: # Bad file descriptor at C:\Perl\scripts\test5.pl line 20.

Note that strict is being used.
Why is $_, above, allowed to be used as a Filehandle? In the other contexts, open() or print (), the script would have failed with appropriate messages that 'String ('F') can't be used ..' etc.

So, close() doesn't expect the same strictness that open() does. Is that as it ought to be?
(ActiveState perl 5.6.1)
mkmcconn


In reply to unexpected close() success on (non-) filehandle by mkmcconn

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others having an uproarious good time at the Monastery: (2)
As of 2023-06-03 18:32 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    How often do you go to conferences?






    Results (16 votes). Check out past polls.

    Notices?