File: tcllib_coroutine.man

package info (click to toggle)
tcllib 1.20%2Bdfsg-1
  • links: PTS
  • area: main
  • in suites: bullseye
  • size: 68,064 kB
  • sloc: tcl: 216,842; ansic: 14,250; sh: 2,846; xml: 1,766; yacc: 1,145; pascal: 881; makefile: 107; perl: 84; f90: 84; python: 33; ruby: 13; php: 11
file content (117 lines) | stat: -rw-r--r-- 4,033 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
[comment {-*- tcl -*- doctools manpage}]
[vset CORO_VERSION 1.2]
[manpage_begin coroutine n [vset CORO_VERSION]]
[keywords after]
[keywords channel]
[keywords coroutine]
[keywords events]
[keywords exit]
[keywords gets]
[keywords global]
[keywords {green threads}]
[keywords read]
[keywords threads]
[keywords update]
[keywords vwait]
[copyright {2010-2015 Andreas Kupries <andreas_kupries@users.sourceforge.net>}]
[moddesc   {Coroutine utilities}]
[category  Coroutine]
[titledesc {Coroutine based event and IO handling}]
[require Tcl 8.6]
[require coroutine [vset CORO_VERSION]]
[description]

The [package coroutine] package provides coroutine-aware
implementations of various event- and channel related commands. It can
be in multiple modes:

[list_begin enumerated]

[enum] Call the commands through their ensemble, in code which is
explicitly written for use within coroutines.

[enum] Import the commands into a namespace, either directly, or
through [cmd {namespace path}]. This allows the use from within code
which is not coroutine-aware per se and restricted to specific
namespaces.

[list_end]

A more agressive form of making code coroutine-oblivious than point 2
above is available through the package [package coroutine::auto],
which intercepts the relevant builtin commands and changes their
implementation dependending on the context they are run in, i.e.
inside or outside of a coroutine.

[section API]

All the commands listed below are synchronous with respect to the
coroutine invoking them, i.e. this coroutine blocks until the result
is available. The overall eventloop is not blocked however.

[list_begin definitions]

[call [cmd {coroutine::util after}] [arg delay]]

This command delays the coroutine invoking it by [arg delay]
milliseconds.

[call [cmd {coroutine::util await}] [arg varname]...]

This command is an extension form of the [cmd {coroutine::util vwait}]
command (see below) which waits on a write to one of many named
namespace variables.

[call [cmd {coroutine::util create}] [arg arg]...]

This command creates a new coroutine with an automatically assigned
name and causes it to run the code specified by the arguments.

[call [cmd {coroutine::util exit}] [opt [arg status]]]

This command exits the current coroutine, causing it to return
[arg status]. If no status was specified the default [arg 0] is
returned.

[call [cmd {coroutine::util gets}] [arg chan] [opt [arg varname]]]

This command reads a line from the channel [arg chan] and returns it
either as its result, or, if a [arg varname] was specified, writes it
to the named variable and returns the number of characters read.

[call [cmd {coroutine::util gets_safety}] [arg chan] [arg limit] [arg varname]]

This command reads a line from the channel [arg chan] up to size [arg limit]
and stores the result in [arg varname]. Of [arg limit] is reached before the
set first newline, an error is thrown. The command returns the number of
characters read.

[call [cmd {coroutine::util global}] [arg varname]...]

This command imports the named global variables of the coroutine into
the current scope. From the technical point of view these variables
reside in level [const #1] of the Tcl stack. I.e. these are not the
regular global variable in to the global namespace, and each coroutine
can have their own set, independent of all others.

[call [cmd {coroutine::util read}] [option -nonewline] [arg chan] [opt [arg n]]]

This command reads [arg n] characters from the channel [arg chan] and
returns them as its result. If [arg n] is not specified the command
will read the channel until EOF is reached.

[call [cmd {coroutine::util update}] [opt [const idletasks]]]

This command causes the coroutine invoking it to run pending events or
idle handlers before proceeding.

[call [cmd {coroutine::util vwait}] [arg varname]]

This command causes the coroutine calling it to wait for a write to
the named namespace variable [arg varname].

[list_end]

[vset CATEGORY coroutine]
[include ../common-text/feedback.inc]
[manpage_end]