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8.112. FileHandle

Provides object methods for working with filehandles. Provides the following methods.

new

$fh = new FileHandle [filename[, mode]]

Constructor. Creates a FileHandle, which is a reference to a newly created symbol. The optional parameters, filename and mode, are passed to open. The FileHandle object is returned if the open succeeds; otherwise, it is destroyed.

new_from_fd

$fh = new_from_fd FileHandle fd, mode

Constructor. Creates a FileHandle, but it takes the file descriptor, fd, instead of filename as a parameter, along with mode; the parameters are required.

fdopen

$fh->fdopen fdname [openmode]

Like open, except that its first parameter is not a filename but a filehandle name, a FileHandle object, or a file descriptor number.

getpos

$pos = $fh->getpos

If the C functions fgetpos(3) and fsetpos(3) are available, getpos returns the current position, $pos, of the FileHandle.

open

$fh->open filename [openmode]

Takes filename and, optionally, the open mode, and opens a file. If the mode is present, it can be in Perl form (e.g., >, +<) or in POSIX form (e.g., w, r+).

setpos

$fh->setpos pos

Uses the value (pos) returned by getpos to restore a previous position of the FileHandle.

setvbuf

$fh->setvbuf(params)

Takes the same parameters as the C function setvbuf(3) and uses the C function to set the buffering policy for the FileHandle.

The following additional FileHandle methods act as front-ends for the corresponding built-in Perl functions (see the O'Reilly book Programming Perl or the perlfunc manpage for more details):

clearerr

getc

gets

eof

seek

fileno

tell

The next group of FileHandle methods correspond to Perl special variables (see Programming Perl or the perlvar manpage):

autoflush

format_page_number

format_formfeed

format_top_name

format_line_break_characters

input_line_number

format_lines_left

input_record_separator

format_lines_per_page

output_field_separator

format_name

output_record_separator

Finally, the following methods are useful:

$fh->print See Perl's built-in print function.

$fh->printf See Perl's built-in printf function.

$fh->getline Works like Perl's <FILEHANDLE> construct, except that it can be safely called in an array context (but it still returns just one line).

$fh->getlines Works like Perl's <FILEHANDLE> construct when called in an array context to read all remaining lines in a file.


8.111. FileCache		8.113. Filter::Simple