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IO::File(3pm)                         Perl Programmers Reference Guide                         IO::File(3pm)



NAME
       IO::File - supply object methods for filehandles

SYNOPSIS
           use IO::File;

           $fh = IO::File->new();
           if ($fh->open("< file")) {
               print <$fh>;
               $fh->close;
           }

           $fh = IO::File->new("> file");
           if (defined $fh) {
               print $fh "bar\n";
               $fh->close;
           }

           $fh = IO::File->new("file", "r");
           if (defined $fh) {
               print <$fh>;
               undef $fh;       # automatically closes the file
           }

           $fh = IO::File->new("file", O_WRONLY|O_APPEND);
           if (defined $fh) {
               print $fh "corge\n";

               $pos = $fh->getpos;
               $fh->setpos($pos);

               undef $fh;       # automatically closes the file
           }

           autoflush STDOUT 1;

DESCRIPTION
       "IO::File" inherits from "IO::Handle" and "IO::Seekable". It extends these classes with methods that
       are specific to file handles.

CONSTRUCTOR
       new ( FILENAME [,MODE [,PERMS]] )
           Creates an "IO::File".  If it receives any parameters, they are passed to the method "open"; if
           the open fails, the object is destroyed.  Otherwise, it is returned to the caller.

       new_tmpfile
           Creates an "IO::File" opened for read/write on a newly created temporary file.  On systems where
           this is possible, the temporary file is anonymous (i.e. it is unlinked after creation, but held
           open).  If the temporary file cannot be created or opened, the "IO::File" object is destroyed.
           Otherwise, it is returned to the caller.

METHODS
       open( FILENAME [,MODE [,PERMS]] )
       open( FILENAME, IOLAYERS )
           "open" accepts one, two or three parameters.  With one parameter, it is just a front end for the
           built-in "open" function.  With two or three parameters, the first parameter is a filename that
           may include whitespace or other special characters, and the second parameter is the open mode,
           optionally followed by a file permission value.

           If "IO::File::open" receives a Perl mode string (">", "+<", etc.)  or an ANSI C fopen() mode
           string ("w", "r+", etc.), it uses the basic Perl "open" operator (but protects any special
           characters).

           If "IO::File::open" is given a numeric mode, it passes that mode and the optional permissions
           value to the Perl "sysopen" operator.  The permissions default to 0666.

           If "IO::File::open" is given a mode that includes the ":" character, it passes all the three
           arguments to the three-argument "open" operator.

           For convenience, "IO::File" exports the O_XXX constants from the Fcntl module, if this module is
           available.

       binmode( [LAYER] )
           "binmode" sets "binmode" on the underlying "IO" object, as documented in "perldoc -f binmode".

           "binmode" accepts one optional parameter, which is the layer to be passed on to the "binmode"
           call.

NOTE
       Some operating systems may perform  "IO::File::new()" or "IO::File::open()" on a directory without
       errors.  This behavior is not portable and not suggested for use.  Using "opendir()" and "readdir()"
       or "IO::Dir" are suggested instead.

SEE ALSO
       perlfunc, "I/O Operators" in perlop, IO::Handle, IO::Seekable, IO::Dir

HISTORY
       Derived from FileHandle.pm by Graham Barr <gbarr@pobox.com>.



perl v5.16.2                                     2012-10-11                                    IO::File(3pm)