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diff --git a/usr/man/mann/read.n b/usr/man/mann/read.n new file mode 100755 index 000000000..7829f652e --- /dev/null +++ b/usr/man/mann/read.n @@ -0,0 +1,352 @@ +'\" +'\" 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 read n 8.1 Tcl "Tcl Built-In Commands" +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +read \- Read from a channel +.SH SYNOPSIS +\fBread \fR?\fB\-nonewline\fR? \fIchannelId\fR +.sp +\fBread \fIchannelId numChars\fR +.BE + +.SH DESCRIPTION +.PP +In the first form, the \fBread\fR command reads all of the data from +\fIchannelId\fR up to the end of the file. If the \fB\-nonewline\fR +switch is specified then the last character of the file is discarded +if it is a newline. In the second form, the extra argument specifies +how many characters to read. Exactly that many characters will be +read and returned, unless there are fewer than \fInumChars\fR left in +the file; in this case all the remaining characters are returned. If +the channel is configured to use a multi-byte encoding, then the +number of characters read may not be the same as the number of bytes +read. +.PP +\fIChannelId\fR must be an identifier for an open channel such as the +Tcl standard input channel (\fBstdin\fR), the return value from an +invocation of \fBopen\fR or \fBsocket\fR, or the result of a channel +creation command provided by a Tcl extension. The channel must have +been opened for input. +.PP +If \fIchannelId\fR is in nonblocking mode, the command may not read as +many characters as requested: once all available input has been read, +the command will return the data that is available rather than +blocking for more input. If the channel is configured to use a +multi-byte encoding, then there may actually be some bytes remaining +in the internal buffers that do not form a complete character. These +bytes will not be returned until a complete character is available or +end-of-file is reached. The \fB\-nonewline\fR switch is ignored if +the command returns before reaching the end of the file. +.PP +\fBRead\fR translates end-of-line sequences in the input into +newline characters according to the \fB\-translation\fR option +for the channel. +See the \fBfconfigure\fR manual entry for a discussion on ways in +which \fBfconfigure\fR will alter input. + +.SH "USE WITH SERIAL PORTS" +'\" Note: this advice actually applies to many versions of Tcl + +For most applications a channel connected to a serial port should be +configured to be nonblocking: \fBfconfigure \fIchannelId \fB\-blocking +\fI0\fR. Then \fBread\fR behaves much like described above. Care +must be taken when using \fBread\fR on blocking serial ports: +.TP +\fBread \fIchannelId numChars\fR +In this form \fBread\fR blocks until \fInumChars\fR have been received +from the serial port. +.TP +\fBread \fIchannelId\fR +In this form \fBread\fR blocks until the reception of the end-of-file +character, see \fBfconfigure -eofchar\fR. If there no end-of-file +character has been configured for the channel, then \fBread\fR will +block forever. +.SH "EXAMPLE" +This example code reads a file all at once, and splits it into a list, +with each line in the file corresponding to an element in the list: +.CS +set fl [open /proc/meminfo] +set data [\fBread\fR $fl] +close $fl +set lines [split $data \en] +.CE + +.SH "SEE ALSO" +file(n), eof(n), fblocked(n), fconfigure(n), Tcl_StandardChannels(3) + +.SH KEYWORDS +blocking, channel, end of line, end of file, nonblocking, read, translation, encoding |