Windows PowerShell command on Get-command tcl

Manual Pages for UNIX Operating System command usage for man tcl_startOfPreviousWord

Tcl Built-In Commands library(1T)

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NAME

auto_execok, auto_import, auto_load, auto_mkindex,

auto_mkindex_old, auto_qualify, auto_reset, tcl_findLibrary,

parray, tcl_endOfWord, tcl_startOfNextWord,

tcl_startOfPreviousWord, tcl_wordBreakAfter,

tcl_wordBreakBefore - standard library of Tcl procedures

SYNOPSIS

auto_execok cmd

auto_import pattern

auto_load cmd

auto_mkindex dir pattern pattern ...

auto_mkindex_old dir pattern pattern ...

auto_qualify command namespace

auto_reset

tcl_findLibrary basename version patch initScript enVarName varName

parray arrayName

tcl_endOfWord str start |

tcl_startOfNextWord str start |

tcl_startOfPreviousWord str start |

tcl_wordBreakAfter str start |

tcl_wordBreakBefore str start |

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INTRODUCTION

Tcl includes a library of Tcl procedures for commonly-needed

functions. The procedures defined in the Tcl library are

generic ones suitable for use by many different applica-

tions. The location of the Tcl library is returned by the info library command. In addition to the Tcl library, each application will normally have its own library of support

procedures as well; the location of this library is nor-

mally given by the value of the $app_library global vari-

able, where app is the name of the application. For exam-

ple, the location of the Tk library is kept in the variable

$tk_library.

To access the procedures in the Tcl library, an application should source the file init.tcl in the library, for example with the Tcl command source [file join [info library] init.tcl]

If the library procedure Tcl_Init is invoked from an

application's Tcl_AppInit procedure, this happens automati-

cally. The code in init.tcl will define the unknown pro-

cedure and arrange for the other procedures to be loaded

on-demand using the auto-load mechanism defined below.

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Tcl Built-In Commands library(1T)

COMMAND PROCEDURES The following procedures are provided in the Tcl library:

auto_execok cmd

Determines whether there is an executable file or shell builtin by the name cmd. If so, it returns a list of

arguments to be passed to exec to execute the execut-

able file or shell builtin named by cmd. If not, it returns an empty string. This command examines the directories in the current search path (given by the

PATH environment variable) in its search for an execut-

able file named cmd. On Windows platforms, the search

is expanded with the same directories and file exten-

sions as used by exec. Auto_exec remembers information

about previous searches in an array named auto_execs;

this avoids the path search in future calls for the

same cmd. The command auto_reset may be used to force

auto_execok to forget its cached information.

auto_import pattern

Auto_import is invoked during namespace import to see

if the imported commands specified by pattern reside in an autoloaded library. If so, the commands are loaded so that they will be available to the interpreter for creating the import links. If the commands do not

reside in an autoloaded library, auto_import does noth-

ing. The pattern matching is performed according to the matching rules of namespace import.

auto_load cmd

This command attempts to load the definition for a Tcl

command named cmd. To do this, it searches an auto-

load path, which is a list of one or more directories.

The auto-load path is given by the global variable

$auto_path if it exists. If there is no $auto_path

variable, then the TCLLIBPATH environment variable is

used, if it exists. Otherwise the auto-load path con-

sists of just the Tcl library directory. Within each

directory in the auto-load path there must be a file

tclIndex that describes one or more commands defined in that directory and a script to evaluate to load each of the commands. The tclIndex file should be generated

with the auto_mkindex command. If cmd is found in an

index file, then the appropriate script is evaluated to

create the command. The auto_load command returns 1 if

cmd was successfully created. The command returns 0 if there was no index entry for cmd or if the script

didn't actually define cmd (e.g. because index informa-

tion is out of date). If an error occurs while pro-

cessing the script, then that error is returned.

Auto_load only reads the index information once and

saves it in the array auto_index; future calls to

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Tcl Built-In Commands library(1T)

auto_load check for cmd in the array rather than re-

reading the index files. The cached index information

may be deleted with the command auto_reset. This will

force the next auto_load command to reload the index

database from disk.

auto_mkindex dir pattern pattern ...

Generates an index suitable for use by auto_load. The

command searches dir for all files whose names match any of the pattern arguments (matching is done with the

glob command), generates an index of all the Tcl com-

mand procedures defined in all the matching files, and stores the index information in a file named tclIndex in dir. If no pattern is given a pattern of *.tcl will be assumed. For example, the command

auto_mkindex foo *.tcl

will read all the .tcl files in subdirectory foo and generate a new index file foo/tclIndex.

Auto_mkindex parses the Tcl scripts by sourcing them

into a slave interpreter and monitoring the proc and namespace commands that are executed. Extensions can

use the (undocumented) auto_mkindex_parser package to

auto_load index. You will have to read through auto.tcl

to see how this works.

Auto_mkindex_old parses the Tcl scripts in a relatively

unsophisticated way: if any line contains the word proc as its first characters then it is assumed to be a procedure definition and the next word of the line is taken as the procedure's name. Procedure definitions that don't appear in this way (e.g. they have spaces before the proc) will not be indexed. If your script

contains "dangerous" code, such as global initializa-

tion code or procedure names with special characters

like $, *, [ or ], you are safer using

auto_mkindex_old.

auto_reset

Destroys all the information cached by auto_execok and

auto_load. This information will be re-read from disk

the next time it is needed. Auto_reset also deletes

any procedures listed in the auto-load index, so that

fresh copies of them will be loaded the next time that they're used.

auto_qualify command namespace

Computes a list of fully qualified names for command. This list mirrors the path a standard Tcl interpreter follows for command lookups: first it looks for the Tcl Last change: 8.0 3

Tcl Built-In Commands library(1T)

command in the current namespace, and then in the glo-

bal namespace. Accordingly, if command is relative and

namespace is not ::, the list returned has two ele-

ments: command scoped by namespace, as if it were a command in the namespace namespace; and command as if it were a command in the global namespace. Otherwise, if either command is absolute (it begins with ::), or namespace is ::, the list contains only command as if it were a command in the global namespace.

Auto_qualify is used by the auto-loading facilities in

Tcl, both for producing auto-loading indexes such as

pkgIndex.tcl, and for performing the actual auto-

loading of functions at runtime. Name

tcl_findLibrary basename version patch initScript enVarName var-

This is a standard search procedure for use by exten-

sions during their initialization. They call this pro-

cedure to look for their script library in several standard directories. The last component of the name of the library directory is normally basenameversion (e.g., tk8.0), but it might be "library" when in the build hierarchies. The initScript file will be sourced into the interpreter once it is found. The directory in which this file is found is stored into the global variable varName. If this variable is already defined (e.g., by C code during application initialization) then no searching is done. Otherwise the search looks in these directories: the directory named by the environment variable enVarName; relative to the Tcl library directory; relative to the executable file in the standard installation bin or bin/arch directory; relative to the executable file in the current build tree; relative to the executable file in a parallel build tree. parray arrayName Prints on standard output the names and values of all the elements in the array arrayName. ArrayName must be an array accessible to the caller of parray. It may be either local or global.

tcl_endOfWord str start

Returns the index of the first end-of-word location |

that occurs after a starting index start in the string |

str. An end-of-word location is defined to be the |

first non-word character following the first word char- |

acter after the starting point. Returns -1 if there |

are no more end-of-word locations after the starting |

point. See the description of tcl_wordchars and |

tcl_nonwordchars below for more details on how Tcl |

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Tcl Built-In Commands library(1T)

determines which characters are word characters. |

tcl_startOfNextWord str start ||

Returns the index of the first start-of-word location |

that occurs after a starting index start in the string |

str. A start-of-word location is defined to be the |

first word character following a non-word character. |

Returns -1 if there are no more start-of-word locations |

after the starting point. |

tcl_startOfPreviousWord str start ||

Returns the index of the first start-of-word location |

that occurs before a starting index start in the string |

str. Returns -1 if there are no more start-of-word |

locations before the starting point. |

tcl_wordBreakAfter str start ||

Returns the index of the first word boundary after the |

starting index start in the string str. Returns -1 if |

there are no more boundaries after the starting point | in the given string. The index returned refers to the | second character of the pair that comprises a boundary. |

tcl_wordBreakBefore str start ||

Returns the index of the first word boundary before the |

starting index start in the string str. Returns -1 if |

there are no more boundaries before the starting point | in the given string. The index returned refers to the | second character of the pair that comprises a boundary. VARIABLES The following global variables are defined or used by the procedures in the Tcl library:

auto_execs

Used by auto_execok to record information about whether

particular commands exist as executable files.

auto_index

Used by auto_load to save the index information read

from disk.

auto_noexec

If set to any value, then unknown will not attempt to

auto-exec any commands.

auto_noload

If set to any value, then unknown will not attempt to

auto-load any commands.

auto_path

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Tcl Built-In Commands library(1T)

If set, then it must contain a valid Tcl list giving

directories to search during auto-load operations.

This variable is initialized during startup to contain, in order: the directories listed in the TCLLIBPATH environment variable, the directory named by the

$tcl_library variable, the parent directory of

$tcl_library, the directories listed in the

$tcl_pkgPath variable.

env(TCL_LIBRARY)

If set, then it specifies the location of the directory containing library scripts (the value of this variable

will be assigned to the tcl_library variable and there-

fore returned by the command info library). If this variable isn't set then a default value is used. env(TCLLIBPATH) If set, then it must contain a valid Tcl list giving

directories to search during auto-load operations.

Directories must be specified in Tcl format, using "/" as the path separator, regardless of platform. This

variable is only used when initializing the auto_path

variable.

tcl_nonwordchars

This variable contains a regular expression that is |

used by routines like tcl_endOfWord to identify whether |

a character is part of a word or not. If the pattern | matches a character, the character is considered to be |

a non-word character. On Windows platforms, spaces, |

tabs, and newlines are considered non-word characters. |

Under Unix, everything but numbers, letters and under- |

scores are considered non-word characters. |

tcl_wordchars ||

This variable contains a regular expression that is |

used by routines like tcl_endOfWord to identify whether |

a character is part of a word or not. If the pattern | matches a character, the character is considered to be | a word character. On Windows platforms, words are | comprised of any character that is not a space, tab, or | newline. Under Unix, words are comprised of numbers, | letters or underscores.

unknown_pending

Used by unknown to record the command(s) for which it is searching. It is used to detect errors where unknown recurses on itself infinitely. The variable is unset before unknown returns. Tcl Last change: 8.0 6

Tcl Built-In Commands library(1T)

ATTRIBUTES

See attributes(5) for descriptions of the following attri-

butes:

_______________________________________

| ATTRIBUTE TYPE | ATTRIBUTE VALUE|

|____________________|__________________|_

| Availability | runtime/tcl-8 |

|____________________|__________________|_

| Interface Stability| Uncommitted |

|____________________|_________________|

NOTES Source for Tcl is available on http://opensolaris.org. Tcl Last change: 8.0 7

Manual Pages for UNIX Operating System command usage for man tcl_startOfPreviousWord

NAME

tcl_startOfPreviousWord, tcl_wordBreakAfter,

SYNOPSIS

tcl_startOfPreviousWord str start |

tcl_startOfPreviousWord str start ||

SEE ALSO

ATTRIBUTES

| ATTRIBUTE TYPE | ATTRIBUTE VALUE|