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I ran into this problem in the past when trying to allow a function to accept filenames or filehandles.

From my testing at the time I don't think it is possible to determine if a scalar is a filehandle or not. As you point out the IO:: objects would be difficult to handle.

The solution that I can up with was just to assume that any references passed to the function were filehandles and any scalars were filenames. Here is an extract from the code.

# If the filename is a reference it is assumed that it is a valid # filehandle, if not we create a filehandle. # if (ref($OLEfile)) { $fh = $OLEfile; } else { # Create a new file, open for writing $fh = FileHandle->new("> $OLEfile"); if (not defined $fh) { croak "Can't open $OLEfile. ......"; } # binmode file whether platform requires it or not binmode($fh); } # Store the filehandle $self->{_filehandle} = $fh;
This isn't bullet-proof but if the documentation is explicit then it may be sufficient.

--
John.


In reply to Re: Re: Re: File::Grep by jmcnamara
in thread File::Grep by Masem

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