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NAME

IO::Wrap - wrap raw filehandles in IO::Handle interface
 

SYNOPSIS

   use IO::Wrap;

   ### Do stuff with any kind of filehandle (including a bare globref), or 
   ### any kind of blessed object that responds to a print() message.
   ###
   sub do_stuff {
       my $fh = shift;

       ### At this point, we have no idea what the user gave us... 
       ### a globref? a FileHandle? a scalar filehandle name?

       $fh = wraphandle($fh);

       ### At this point, we know we have an IO::Handle-like object!

       $fh->print("Hey there!");
       ...
   }

DESCRIPTION

    do_stuff(\*STDOUT);
    do_stuff('STDERR');
    do_stuff($some_FileHandle_object);
    do_stuff($some_IO_Handle_object);

And even:

    do_stuff($any_object_with_a_print_method);

Sure, one way to do it is to force the caller to use tiehandle(). But that puts the burden on them. Another way to do it is to use IO::Wrap, which provides you with the following functions:

wraphandle SCALAR

This function will take a single argument, and ``wrap'' it based on what it seems to be...

*

A raw scalar filehandle name, like "STDOUT" or "Class::HANDLE". In this case, the filehandle name is wrapped in an IO::Wrap object, which is returned.

*

A raw filehandle glob, like "\*STDOUT". In this case, the filehandle glob is wrapped in an IO::Wrap object, which is returned.

*

A blessed FileHandle object. In this case, the FileHandle is wrapped in an IO::Wrap object if and only if your FileHandle class does not support the "read()" method.

*

Any other kind of blessed object, which is assumed to be already conformant to the IO::Handle interface. In this case, you just get back that object.

If you get back an IO::Wrap object, it will obey a basic subset of the IO:: interface. That is, the following methods (note: I said methods, not named operators) should work on the thing you get back:

    close 
    getline 
    getlines 
    print ARGS...
    read BUFFER,NBYTES
    seek POS,WHENCE
    tell

NOTES

When wrapping a FileHandle object, however, I believe that Perl will invoke the FileHandle::DESTROY when the last reference goes away, so in that case, the filehandle is closed if the wrapped FileHandle really was the last reference to it.  

WARNINGS

VERSION

AUTHOR

Index

NAME

SYNOPSIS

DESCRIPTION

NOTES

WARNINGS

VERSION

AUTHOR

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