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


       IO::File - supply object methods for filehandles


           use IO::File;

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

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

           $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;

               undef $fh;       # automatically closes the file

           autoflush STDOUT 1;


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


       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.

           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


       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.


       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.


       perlfunc(1), "I/O Operators" in perlop(1), IO::Handle(3),
       IO::Seekable(3), IO::Dir(3)


       Derived from by Graham Barr <>.

perl v5.24.0                      2015-10-14                     IO::File(3pm)

perl 5.24 - Generated Sun Nov 13 16:32:09 CST 2016
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