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diff --git a/usr/man/mann/unknown.n b/usr/man/mann/unknown.n new file mode 100755 index 000000000..6dad8db92 --- /dev/null +++ b/usr/man/mann/unknown.n @@ -0,0 +1,357 @@ +'\" +'\" Copyright (c) 1993 The Regents of the University of California. +'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +.\" The -*- nroff -*- definitions below are for supplemental macros used +.\" in Tcl/Tk manual entries. +.\" +.\" .AP type name in/out ?indent? +.\" Start paragraph describing an argument to a library procedure. +.\" type is type of argument (int, etc.), in/out is either "in", "out", +.\" or "in/out" to describe whether procedure reads or modifies arg, +.\" and indent is equivalent to second arg of .IP (shouldn't ever be +.\" needed; use .AS below instead) +.\" +.\" .AS ?type? ?name? +.\" Give maximum sizes of arguments for setting tab stops. Type and +.\" name are examples of largest possible arguments that will be passed +.\" to .AP later. If args are omitted, default tab stops are used. +.\" +.\" .BS +.\" Start box enclosure. From here until next .BE, everything will be +.\" enclosed in one large box. +.\" +.\" .BE +.\" End of box enclosure. +.\" +.\" .CS +.\" Begin code excerpt. +.\" +.\" .CE +.\" End code excerpt. +.\" +.\" .VS ?version? ?br? +.\" Begin vertical sidebar, for use in marking newly-changed parts +.\" of man pages. The first argument is ignored and used for recording +.\" the version when the .VS was added, so that the sidebars can be +.\" found and removed when they reach a certain age. If another argument +.\" is present, then a line break is forced before starting the sidebar. +.\" +.\" .VE +.\" End of vertical sidebar. +.\" +.\" .DS +.\" Begin an indented unfilled display. +.\" +.\" .DE +.\" End of indented unfilled display. +.\" +.\" .SO ?manpage? +.\" Start of list of standard options for a Tk widget. The manpage +.\" argument defines where to look up the standard options; if +.\" omitted, defaults to "options". The options follow on successive +.\" lines, in three columns separated by tabs. +.\" +.\" .SE +.\" End of list of standard options for a Tk widget. +.\" +.\" .OP cmdName dbName dbClass +.\" Start of description of a specific option. cmdName gives the +.\" option's name as specified in the class command, dbName gives +.\" the option's name in the option database, and dbClass gives +.\" the option's class in the option database. +.\" +.\" .UL arg1 arg2 +.\" Print arg1 underlined, then print arg2 normally. +.\" +.\" .QW arg1 ?arg2? +.\" Print arg1 in quotes, then arg2 normally (for trailing punctuation). +.\" +.\" .PQ arg1 ?arg2? +.\" Print an open parenthesis, arg1 in quotes, then arg2 normally +.\" (for trailing punctuation) and then a closing parenthesis. +.\" +.\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages. +.if t .wh -1.3i ^B +.nr ^l \n(.l +.ad b +.\" # Start an argument description +.de AP +.ie !"\\$4"" .TP \\$4 +.el \{\ +. ie !"\\$2"" .TP \\n()Cu +. el .TP 15 +.\} +.ta \\n()Au \\n()Bu +.ie !"\\$3"" \{\ +\&\\$1 \\fI\\$2\\fP (\\$3) +.\".b +.\} +.el \{\ +.br +.ie !"\\$2"" \{\ +\&\\$1 \\fI\\$2\\fP +.\} +.el \{\ +\&\\fI\\$1\\fP +.\} +.\} +.. +.\" # define tabbing values for .AP +.de AS +.nr )A 10n +.if !"\\$1"" .nr )A \\w'\\$1'u+3n +.nr )B \\n()Au+15n +.\" +.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n +.nr )C \\n()Bu+\\w'(in/out)'u+2n +.. +.AS Tcl_Interp Tcl_CreateInterp in/out +.\" # BS - start boxed text +.\" # ^y = starting y location +.\" # ^b = 1 +.de BS +.br +.mk ^y +.nr ^b 1u +.if n .nf +.if n .ti 0 +.if n \l'\\n(.lu\(ul' +.if n .fi +.. +.\" # BE - end boxed text (draw box now) +.de BE +.nf +.ti 0 +.mk ^t +.ie n \l'\\n(^lu\(ul' +.el \{\ +.\" Draw four-sided box normally, but don't draw top of +.\" box if the box started on an earlier page. +.ie !\\n(^b-1 \{\ +\h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul' +.\} +.el \}\ +\h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul' +.\} +.\} +.fi +.br +.nr ^b 0 +.. +.\" # VS - start vertical sidebar +.\" # ^Y = starting y location +.\" # ^v = 1 (for troff; for nroff this doesn't matter) +.de VS +.if !"\\$2"" .br +.mk ^Y +.ie n 'mc \s12\(br\s0 +.el .nr ^v 1u +.. +.\" # VE - end of vertical sidebar +.de VE +.ie n 'mc +.el \{\ +.ev 2 +.nf +.ti 0 +.mk ^t +\h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n' +.sp -1 +.fi +.ev +.\} +.nr ^v 0 +.. +.\" # Special macro to handle page bottom: finish off current +.\" # box/sidebar if in box/sidebar mode, then invoked standard +.\" # page bottom macro. +.de ^B +.ev 2 +'ti 0 +'nf +.mk ^t +.if \\n(^b \{\ +.\" Draw three-sided box if this is the box's first page, +.\" draw two sides but no top otherwise. +.ie !\\n(^b-1 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c +.el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c +.\} +.if \\n(^v \{\ +.nr ^x \\n(^tu+1v-\\n(^Yu +\kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c +.\} +.bp +'fi +.ev +.if \\n(^b \{\ +.mk ^y +.nr ^b 2 +.\} +.if \\n(^v \{\ +.mk ^Y +.\} +.. +.\" # DS - begin display +.de DS +.RS +.nf +.sp +.. +.\" # DE - end display +.de DE +.fi +.RE +.sp +.. +.\" # SO - start of list of standard options +.de SO +'ie '\\$1'' .ds So \\fBoptions\\fR +'el .ds So \\fB\\$1\\fR +.SH "STANDARD OPTIONS" +.LP +.nf +.ta 5.5c 11c +.ft B +.. +.\" # SE - end of list of standard options +.de SE +.fi +.ft R +.LP +See the \\*(So manual entry for details on the standard options. +.. +.\" # OP - start of full description for a single option +.de OP +.LP +.nf +.ta 4c +Command-Line Name: \\fB\\$1\\fR +Database Name: \\fB\\$2\\fR +Database Class: \\fB\\$3\\fR +.fi +.IP +.. +.\" # CS - begin code excerpt +.de CS +.RS +.nf +.ta .25i .5i .75i 1i +.. +.\" # CE - end code excerpt +.de CE +.fi +.RE +.. +.\" # UL - underline word +.de UL +\\$1\l'|0\(ul'\\$2 +.. +.\" # QW - apply quotation marks to word +.de QW +.ie '\\*(lq'"' ``\\$1''\\$2 +.\"" fix emacs highlighting +.el \\*(lq\\$1\\*(rq\\$2 +.. +.\" # PQ - apply parens and quotation marks to word +.de PQ +.ie '\\*(lq'"' (``\\$1''\\$2)\\$3 +.\"" fix emacs highlighting +.el (\\*(lq\\$1\\*(rq\\$2)\\$3 +.. +.\" # QR - quoted range +.de QR +.ie '\\*(lq'"' ``\\$1''\\-``\\$2''\\$3 +.\"" fix emacs highlighting +.el \\*(lq\\$1\\*(rq\\-\\*(lq\\$2\\*(rq\\$3 +.. +.\" # MT - "empty" string +.de MT +.QW "" +.. +.TH unknown n "" Tcl "Tcl Built-In Commands" +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +unknown \- Handle attempts to use non-existent commands +.SH SYNOPSIS +\fBunknown \fIcmdName \fR?\fIarg arg ...\fR? +.BE +.SH DESCRIPTION +.PP +This command is invoked by the Tcl interpreter whenever a script +tries to invoke a command that does not exist. The default implementation +of \fBunknown\fR is a library procedure defined when Tcl initializes an +interpreter. You can override the default \fBunknown\fR to change its +functionality, or you can register a new handler for individual namespaces +using the \fBnamespace unknown\fR command. Note that there is no default +implementation of \fBunknown\fR in a safe interpreter. +.PP +If the Tcl interpreter encounters a command name for which there +is not a defined command (in either the current namespace, or the +global namespace), then Tcl checks for the existence of +an unknown handler for the current namespace. By default, this +handler is a command named \fB::unknown\fR. If there is no such +command, then the interpreter returns an error. +If the \fBunknown\fR command exists (or a new handler has been +registered for the current namespace), then it is invoked with +arguments consisting of the fully-substituted name and arguments +for the original non-existent command. +The \fBunknown\fR command typically does things like searching +through library directories for a command procedure with the name +\fIcmdName\fR, or expanding abbreviated command names to full-length, +or automatically executing unknown commands as sub-processes. +In some cases (such as expanding abbreviations) \fBunknown\fR will +change the original command slightly and then (re-)execute it. +The result of the \fBunknown\fR command is used as the result for +the original non-existent command. +.PP +The default implementation of \fBunknown\fR behaves as follows. +It first calls the \fBauto_load\fR library procedure to load the command. +If this succeeds, then it executes the original command with its +original arguments. +If the auto-load fails then \fBunknown\fR calls \fBauto_execok\fR +to see if there is an executable file by the name \fIcmd\fR. +If so, it invokes the Tcl \fBexec\fR command +with \fIcmd\fR and all the \fIargs\fR as arguments. +If \fIcmd\fR cannot be auto-executed, \fBunknown\fR checks to +see if the command was invoked at top-level and outside of any +script. If so, then \fBunknown\fR takes two additional steps. +First, it sees if \fIcmd\fR has one of the following three forms: +\fB!!\fR, \fB!\fIevent\fR, or \fB^\fIold\fB^\fInew\fR?\fB^\fR?. +If so, then \fBunknown\fR carries out history substitution +in the same way that \fBcsh\fR would for these constructs. +Finally, \fBunknown\fR checks to see if \fIcmd\fR is +a unique abbreviation for an existing Tcl command. +If so, it expands the command name and executes the command with +the original arguments. +If none of the above efforts has been able to execute +the command, \fBunknown\fR generates an error return. +If the global variable \fBauto_noload\fR is defined, then the auto-load +step is skipped. +If the global variable \fBauto_noexec\fR is defined then the +auto-exec step is skipped. +Under normal circumstances the return value from \fBunknown\fR +is the return value from the command that was eventually +executed. +.SH EXAMPLE +Arrange for the \fBunknown\fR command to have its standard behavior +except for first logging the fact that a command was not found: +.PP +.CS +# Save the original one so we can chain to it +rename \fBunknown\fR _original_unknown + +# Provide our own implementation +proc \fBunknown\fR args { + puts stderr "WARNING: unknown command: $args" + uplevel 1 [list _original_unknown {*}$args] +} +.CE +.SH "SEE ALSO" +info(n), proc(n), interp(n), library(n), namespace(n) +.SH KEYWORDS +error, non-existent command |