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Diffstat (limited to 'upstream/debian-unstable/man3/IO::Select.3perl')
| -rw-r--r-- | upstream/debian-unstable/man3/IO::Select.3perl | 190 |
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diff --git a/upstream/debian-unstable/man3/IO::Select.3perl b/upstream/debian-unstable/man3/IO::Select.3perl new file mode 100644 index 00000000..25783c07 --- /dev/null +++ b/upstream/debian-unstable/man3/IO::Select.3perl @@ -0,0 +1,190 @@ +.\" -*- 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 "IO::Select 3perl" +.TH IO::Select 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 +IO::Select \- OO interface to the select system call +.SH SYNOPSIS +.IX Header "SYNOPSIS" +.Vb 1 +\& use IO::Select; +\& +\& $s = IO::Select\->new(); +\& +\& $s\->add(\e*STDIN); +\& $s\->add($some_handle); +\& +\& @ready = $s\->can_read($timeout); +\& +\& @ready = IO::Select\->new(@handles)\->can_read(0); +.Ve +.SH DESCRIPTION +.IX Header "DESCRIPTION" +The \f(CW\*(C`IO::Select\*(C'\fR package implements an object approach to the system \f(CW\*(C`select\*(C'\fR +function call. It allows the user to see what IO handles, see IO::Handle, +are ready for reading, writing or have an exception pending. +.SH CONSTRUCTOR +.IX Header "CONSTRUCTOR" +.IP "new ( [ HANDLES ] )" 4 +.IX Item "new ( [ HANDLES ] )" +The constructor creates a new object and optionally initialises it with a set +of handles. +.SH METHODS +.IX Header "METHODS" +.IP "add ( HANDLES )" 4 +.IX Item "add ( HANDLES )" +Add the list of handles to the \f(CW\*(C`IO::Select\*(C'\fR object. It is these values that +will be returned when an event occurs. \f(CW\*(C`IO::Select\*(C'\fR keeps these values in a +cache which is indexed by the \f(CW\*(C`fileno\*(C'\fR of the handle, so if more than one +handle with the same \f(CW\*(C`fileno\*(C'\fR is specified then only the last one is cached. +.Sp +Each handle can be an \f(CW\*(C`IO::Handle\*(C'\fR object, an integer or an array +reference where the first element is an \f(CW\*(C`IO::Handle\*(C'\fR or an integer. +.IP "remove ( HANDLES )" 4 +.IX Item "remove ( HANDLES )" +Remove all the given handles from the object. This method also works +by the \f(CW\*(C`fileno\*(C'\fR of the handles. So the exact handles that were added +need not be passed, just handles that have an equivalent \f(CW\*(C`fileno\*(C'\fR +.IP "exists ( HANDLE )" 4 +.IX Item "exists ( HANDLE )" +Returns a true value (actually the handle itself) if it is present. +Returns undef otherwise. +.IP handles 4 +.IX Item "handles" +Return an array of all registered handles. +.IP "can_read ( [ TIMEOUT ] )" 4 +.IX Item "can_read ( [ TIMEOUT ] )" +Return an array of handles that are ready for reading. \f(CW\*(C`TIMEOUT\*(C'\fR is the +maximum amount of time to wait before returning an empty list (with \f(CW$!\fR +unchanged), in seconds, possibly fractional. If \f(CW\*(C`TIMEOUT\*(C'\fR is not given +and any handles are registered then the call will block indefinitely. +Upon error, an empty list is returned, with \f(CW$!\fR set to indicate the +error. To distinguish between timeout and error, set \f(CW$!\fR to zero +before calling this method, and check it after an empty list is returned. +.IP "can_write ( [ TIMEOUT ] )" 4 +.IX Item "can_write ( [ TIMEOUT ] )" +Same as \f(CW\*(C`can_read\*(C'\fR except check for handles that can be written to. +.IP "has_exception ( [ TIMEOUT ] )" 4 +.IX Item "has_exception ( [ TIMEOUT ] )" +Same as \f(CW\*(C`can_read\*(C'\fR except check for handles that have an exception +condition, for example pending out-of-band data. +.IP "count ()" 4 +.IX Item "count ()" +Returns the number of handles that the object will check for when +one of the \f(CW\*(C`can_\*(C'\fR methods is called or the object is passed to +the \f(CW\*(C`select\*(C'\fR static method. +.IP \fBbits()\fR 4 +.IX Item "bits()" +Return the bit string suitable as argument to the core \fBselect()\fR call. +.IP "select ( READ, WRITE, EXCEPTION [, TIMEOUT ] )" 4 +.IX Item "select ( READ, WRITE, EXCEPTION [, TIMEOUT ] )" +\&\f(CW\*(C`select\*(C'\fR is a static method, that is you call it with the package name +like \f(CW\*(C`new\*(C'\fR. \f(CW\*(C`READ\*(C'\fR, \f(CW\*(C`WRITE\*(C'\fR and \f(CW\*(C`EXCEPTION\*(C'\fR are either \f(CW\*(C`undef\*(C'\fR or +\&\f(CW\*(C`IO::Select\*(C'\fR objects. \f(CW\*(C`TIMEOUT\*(C'\fR is optional and has the same effect as +for the core select call. +.Sp +If at least one handle is ready for the specified kind of operation, +the result will be an array of 3 elements, each a reference to an array +which will hold the handles that are ready for reading, writing and +have exceptions respectively. Upon timeout, an empty list is returned, +with \f(CW$!\fR unchanged. Upon error, an empty list is returned, with \f(CW$!\fR +set to indicate the error. To distinguish between timeout and error, +set \f(CW$!\fR to zero before calling this method, and check it after an +empty list is returned. +.SH EXAMPLE +.IX Header "EXAMPLE" +Here is a short example which shows how \f(CW\*(C`IO::Select\*(C'\fR could be used +to write a server which communicates with several sockets while also +listening for more connections on a listen socket +.PP +.Vb 2 +\& use IO::Select; +\& use IO::Socket; +\& +\& $lsn = IO::Socket::INET\->new(Listen => 1, LocalPort => 8080); +\& $sel = IO::Select\->new( $lsn ); +\& +\& while(@ready = $sel\->can_read) { +\& foreach $fh (@ready) { +\& if($fh == $lsn) { +\& # Create a new socket +\& $new = $lsn\->accept; +\& $sel\->add($new); +\& } +\& else { +\& # Process socket +\& +\& # Maybe we have finished with the socket +\& $sel\->remove($fh); +\& $fh\->close; +\& } +\& } +\& } +.Ve +.SH AUTHOR +.IX Header "AUTHOR" +Graham Barr. Currently maintained by the Perl Porters. Please report all +bugs at <https://github.com/Perl/perl5/issues>. +.SH COPYRIGHT +.IX Header "COPYRIGHT" +Copyright (c) 1997\-8 Graham Barr <gbarr@pobox.com>. All rights reserved. +This program is free software; you can redistribute it and/or +modify it under the same terms as Perl itself. |