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Diffstat (limited to 'upstream/debian-unstable/man3/FileHandle.3perl')
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diff --git a/upstream/debian-unstable/man3/FileHandle.3perl b/upstream/debian-unstable/man3/FileHandle.3perl new file mode 100644 index 00000000..ba405db1 --- /dev/null +++ b/upstream/debian-unstable/man3/FileHandle.3perl @@ -0,0 +1,215 @@ +.\" -*- mode: troff; coding: utf-8 -*- +.\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43) +.\" +.\" Standard preamble: +.\" ======================================================================== +.de Sp \" Vertical space (when we can't use .PP) +.if t .sp .5v +.if n .sp +.. +.de Vb \" Begin verbatim text +.ft CW +.nf +.ne \\$1 +.. +.de Ve \" End verbatim text +.ft R +.fi +.. +.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. +.ie n \{\ +. ds C` "" +. ds C' "" +'br\} +.el\{\ +. ds C` +. ds C' +'br\} +.\" +.\" Escape single quotes in literal strings from groff's Unicode transform. +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" +.\" If the F register is >0, we'll generate index entries on stderr for +.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index +.\" entries marked with X<> in POD. Of course, you'll have to process the +.\" output yourself in some meaningful fashion. +.\" +.\" Avoid warning from groff about undefined register 'F'. +.de IX +.. +.nr rF 0 +.if \n(.g .if rF .nr rF 1 +.if (\n(rF:(\n(.g==0)) \{\ +. if \nF \{\ +. de IX +. tm Index:\\$1\t\\n%\t"\\$2" +.. +. if !\nF==2 \{\ +. nr % 0 +. nr F 2 +. \} +. \} +.\} +.rr rF +.\" ======================================================================== +.\" +.IX Title "FileHandle 3perl" +.TH FileHandle 3perl 2024-01-12 "perl v5.38.2" "Perl Programmers Reference Guide" +.\" For nroff, turn off justification. Always turn off hyphenation; it makes +.\" way too many mistakes in technical documents. +.if n .ad l +.nh +.SH NAME +FileHandle \- supply object methods for filehandles +.SH SYNOPSIS +.IX Header "SYNOPSIS" +.Vb 1 +\& use FileHandle; +\& +\& my $fh = FileHandle\->new; +\& if ($fh\->open("< file")) { +\& print <$fh>; +\& $fh\->close; +\& } +\& +\& my $fh = FileHandle\->new("> FOO"); +\& if (defined $fh) { +\& print $fh "bar\en"; +\& $fh\->close; +\& } +\& +\& my $fh = FileHandle\->new("file", "r"); +\& if (defined $fh) { +\& print <$fh>; +\& undef $fh; # automatically closes the file +\& } +\& +\& my $fh = FileHandle\->new("file", O_WRONLY|O_APPEND); +\& if (defined $fh) { +\& print $fh "corge\en"; +\& undef $fh; # automatically closes the file +\& } +\& +\& my $pos = $fh\->getpos; +\& $fh\->setpos($pos); +\& +\& $fh\->setvbuf(my $buffer_var, _IOLBF, 1024); +\& +\& my ($readfh, $writefh) = FileHandle::pipe; +\& +\& autoflush STDOUT 1; +.Ve +.SH DESCRIPTION +.IX Header "DESCRIPTION" +NOTE: This class is now a front-end to the IO::* classes. +.PP +\&\f(CW\*(C`FileHandle::new\*(C'\fR creates a \f(CW\*(C`FileHandle\*(C'\fR, which is a reference to a +newly created symbol (see the Symbol package). If it receives any +parameters, they are passed to \f(CW\*(C`FileHandle::open\*(C'\fR; if the open fails, +the \f(CW\*(C`FileHandle\*(C'\fR object is destroyed. Otherwise, it is returned to +the caller. +.PP +\&\f(CW\*(C`FileHandle::new_from_fd\*(C'\fR creates a \f(CW\*(C`FileHandle\*(C'\fR like \f(CW\*(C`new\*(C'\fR does. +It requires two parameters, which are passed to \f(CW\*(C`FileHandle::fdopen\*(C'\fR; +if the fdopen fails, the \f(CW\*(C`FileHandle\*(C'\fR object is destroyed. +Otherwise, it is returned to the caller. +.PP +\&\f(CW\*(C`FileHandle::open\*(C'\fR accepts one parameter or two. With one parameter, +it is just a front end for the built-in \f(CW\*(C`open\*(C'\fR function. With two +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. +.PP +If \f(CW\*(C`FileHandle::open\*(C'\fR receives a Perl mode string (">", "+<", etc.) +or a POSIX \fBfopen()\fR mode string ("w", "r+", etc.), it uses the basic +Perl \f(CW\*(C`open\*(C'\fR operator. +.PP +If \f(CW\*(C`FileHandle::open\*(C'\fR is given a numeric mode, it passes that mode +and the optional permissions value to the Perl \f(CW\*(C`sysopen\*(C'\fR operator. +For convenience, \f(CW\*(C`FileHandle::import\*(C'\fR tries to import the O_XXX +constants from the Fcntl module. If dynamic loading is not available, +this may fail, but the rest of FileHandle will still work. +.PP +\&\f(CW\*(C`FileHandle::fdopen\*(C'\fR is like \f(CW\*(C`open\*(C'\fR except that its first parameter +is not a filename but rather a file handle name, a FileHandle object, +or a file descriptor number. +.PP +If the C functions \fBfgetpos()\fR and \fBfsetpos()\fR are available, then +\&\f(CW\*(C`FileHandle::getpos\*(C'\fR returns an opaque value that represents the +current position of the FileHandle, and \f(CW\*(C`FileHandle::setpos\*(C'\fR uses +that value to return to a previously visited position. +.PP +If the C function \fBsetvbuf()\fR is available, then \f(CW\*(C`FileHandle::setvbuf\*(C'\fR +sets the buffering policy for the FileHandle. The calling sequence +for the Perl function is the same as its C counterpart, including the +macros \f(CW\*(C`_IOFBF\*(C'\fR, \f(CW\*(C`_IOLBF\*(C'\fR, and \f(CW\*(C`_IONBF\*(C'\fR, except that the buffer +parameter specifies a scalar variable to use as a buffer. WARNING: A +variable used as a buffer by \f(CW\*(C`FileHandle::setvbuf\*(C'\fR must not be +modified in any way until the FileHandle is closed or until +\&\f(CW\*(C`FileHandle::setvbuf\*(C'\fR is called again, or memory corruption may +result! +.PP +See perlfunc for complete descriptions of each of the following +supported \f(CW\*(C`FileHandle\*(C'\fR methods, which are just front ends for the +corresponding built-in functions: +.PP +.Vb 8 +\& close +\& fileno +\& getc +\& gets +\& eof +\& clearerr +\& seek +\& tell +.Ve +.PP +See perlvar for complete descriptions of each of the following +supported \f(CW\*(C`FileHandle\*(C'\fR methods: +.PP +.Vb 12 +\& autoflush +\& output_field_separator +\& output_record_separator +\& input_record_separator +\& input_line_number +\& format_page_number +\& format_lines_per_page +\& format_lines_left +\& format_name +\& format_top_name +\& format_line_break_characters +\& format_formfeed +.Ve +.PP +Furthermore, for doing normal I/O you might need these: +.ie n .IP $fh\->print 4 +.el .IP \f(CW$fh\fR\->print 4 +.IX Item "$fh->print" +See "print" in perlfunc. +.ie n .IP $fh\->printf 4 +.el .IP \f(CW$fh\fR\->printf 4 +.IX Item "$fh->printf" +See "printf" in perlfunc. +.ie n .IP $fh\->getline 4 +.el .IP \f(CW$fh\fR\->getline 4 +.IX Item "$fh->getline" +This works like <$fh> described in "I/O Operators" in perlop +except that it's more readable and can be safely called in a +list context but still returns just one line. +.ie n .IP $fh\->getlines 4 +.el .IP \f(CW$fh\fR\->getlines 4 +.IX Item "$fh->getlines" +This works like <$fh> when called in a list context to +read all the remaining lines in a file, except that it's more readable. +It will also \fBcroak()\fR if accidentally called in a scalar context. +.PP +There are many other functions available since FileHandle is descended +from IO::File, IO::Seekable, and IO::Handle. Please see those +respective pages for documentation on more functions. +.SH "SEE ALSO" +.IX Header "SEE ALSO" +The \fBIO\fR extension, +perlfunc, +"I/O Operators" in perlop. |