Index for Section 3

Alphabetical listing for I

Bottom of page

IO::File(3)
NAME
  IO::File - supply object methods for filehandles

SYNOPSIS
      use IO::File;

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

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

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

      $fh = new IO::File "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>.

Index for Section 3

Alphabetical listing for I

Top of page