Manual Pages for UNIX Darwin command on man IO::File
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Manual Pages for UNIX Darwin command on man IO::File

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

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", OWRONLY|OAPPEND;

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. CCOONNSSTTRRUUCCTTOORR

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. newtmpfile

Creates an "IO::File" opened for read/write on a newly created tem-

porary 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. MMEETTHHOODDSS

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 permis-

sion 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 ":" charac-

ter, it passes all the three arguments to the three-argument "open"

operator.

For convenience, "IO::File" exports the OXXX constants from the

Fcntl module, if this module is available. binmode( [LAYER] )

"binmode" sets "binmode" on the underlying "IO" object, as docu-

mented in "perldoc -f binmode".

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

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 .

perl v5.8.8 2001-09-21 IO::File(3pm)




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