diff options
Diffstat (limited to 'doc/fconfigure.n')
| -rw-r--r-- | doc/fconfigure.n | 83 |
1 files changed, 45 insertions, 38 deletions
diff --git a/doc/fconfigure.n b/doc/fconfigure.n index d455862..8da76c6 100644 --- a/doc/fconfigure.n +++ b/doc/fconfigure.n @@ -1,13 +1,11 @@ -'\" +'\" '\" Copyright (c) 1995-1996 Sun Microsystems, Inc. '\" '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. '\" -'\" RCS: @(#) $Id: fconfigure.n,v 1.15 2006/03/14 22:52:17 andreas_kupries Exp $ -'\" -.so man.macros .TH fconfigure n 8.3 Tcl "Tcl Built-In Commands" +.so man.macros .BS '\" Note: do not modify the .SH NAME line immediately below! .SH NAME @@ -41,7 +39,8 @@ The options described below are supported for all channels. In addition, each channel type may add options that only it supports. See the manual entry for the command that creates each type of channels for the options that that specific type of channel supports. For example, see the manual -entry for the \fBsocket\fR command for its additional options. +entry for the \fBsocket\fR command for additional options for sockets, and +the \fBopen\fR command for additional options for serial devices. .TP \fB\-blocking\fR \fIboolean\fR The \fB\-blocking\fR option determines whether I/O operations on the @@ -73,8 +72,8 @@ initially set to \fBline\fR, and \fBstderr\fR is set to \fBnone\fR. . \fINewvalue\fR must be an integer; its value is used to set the size of buffers, in bytes, subsequently allocated for this channel to store input -or output. \fINewvalue\fR must be between ten and one million, allowing -buffers of ten to one million bytes in size. +or output. \fINewvalue\fR must be between one and one million, allowing +buffers of one to one million bytes in size. .TP \fB\-encoding\fR \fIname\fR . @@ -120,21 +119,24 @@ channel, a two-element list will always be returned. The default value for \fB\-eofchar\fR is the empty string in all cases except for files under Windows. In that case the \fB\-eofchar\fR is Control-z (\ex1a) for reading and the empty string for writing. +The acceptable range for \fB\-eofchar\fR values is \ex01 - \ex7f; +attempting to set \fB\-eofchar\fR to a value outside of this range will +generate an error. .TP \fB\-translation\fR \fImode\fR .TP -\fB\-translation\fR \fB{\fIinMode outMode\fB}\fR +\fB\-translation\fR \fB{\fIinMode outMode\fB}\fR . In Tcl scripts the end of a line is always represented using a single newline character (\en). However, in actual files and devices the end of a line may be represented differently on different platforms, or even for different devices on the same platform. For example, under UNIX newlines are used in files, whereas carriage-return-linefeed sequences are -normally used in network connections. On input (i.e., with \fBgets\fP -and \fBread\fP) the Tcl I/O system automatically translates the external +normally used in network connections. On input (i.e., with \fBgets\fR +and \fBread\fR) the Tcl I/O system automatically translates the external end-of-line representation into newline characters. Upon output (i.e., -with \fBputs\fP), the I/O system translates newlines to the external -end-of-line representation. The default translation mode, \fBauto\fP, +with \fBputs\fR), the I/O system translates newlines to the external +end-of-line representation. The default translation mode, \fBauto\fR, handles all the common cases automatically, but the \fB\-translation\fR option provides explicit control over the end of line translations. .RS @@ -152,8 +154,8 @@ currently supported: \fBauto\fR . As the input translation mode, \fBauto\fR treats any of newline -(\fBlf\fP), carriage return (\fBcr\fP), or carriage return followed by a -newline (\fBcrlf\fP) as the end of line representation. The end of line +(\fBlf\fR), carriage return (\fBcr\fR), or carriage return followed by a +newline (\fBcrlf\fR) as the end of line representation. The end of line representation can even change from line-to-line, and all cases are translated to a newline. As the output translation mode, \fBauto\fR chooses a platform specific representation; for sockets on all platforms @@ -161,15 +163,15 @@ Tcl chooses \fBcrlf\fR, for all Unix flavors, it chooses \fBlf\fR, and for the various flavors of Windows it chooses \fBcrlf\fR. The default setting for \fB\-translation\fR is \fBauto\fR for both input and output. .TP -\fBbinary\fR +\fBbinary\fR . No end-of-line translations are performed. This is nearly identical to -\fBlf\fP mode, except that in addition \fBbinary\fP mode also sets the +\fBlf\fR mode, except that in addition \fBbinary\fR mode also sets the end-of-file character to the empty string (which disables it) and sets the encoding to \fBbinary\fR (which disables encoding filtering). See the description of \fB\-eofchar\fR and \fB\-encoding\fR for more information. -.PP .RS +.PP Internally, i.e. when it comes to the actual behaviour of the translator this value \fBis\fR identical to \fBlf\fR and is therefore reported as such when queried. Even if \fBbinary\fR was used to set @@ -180,17 +182,17 @@ the translation. . The end of a line in the underlying file or device is represented by a single carriage return character. As the input translation mode, -\fBcr\fP mode converts carriage returns to newline characters. As the -output translation mode, \fBcr\fP mode translates newline characters to +\fBcr\fR mode converts carriage returns to newline characters. As the +output translation mode, \fBcr\fR mode translates newline characters to carriage returns. .TP \fBcrlf\fR . The end of a line in the underlying file or device is represented by a carriage return character followed by a linefeed character. As the input -translation mode, \fBcrlf\fP mode converts carriage-return-linefeed +translation mode, \fBcrlf\fR mode converts carriage-return-linefeed sequences to newline characters. As the output translation mode, -\fBcrlf\fP mode translates newline characters to carriage-return-linefeed +\fBcrlf\fR mode translates newline characters to carriage-return-linefeed sequences. This mode is typically used on Windows platforms and for network connections. .TP @@ -212,34 +214,38 @@ If, for example, a Tcl application is started by the \fBinet\fR super-server common on Unix system its Tcl standard channels will be sockets and thus support the socket options. .SH EXAMPLES +.PP Instruct Tcl to always send output to \fBstdout\fR immediately, whether or not it is to a terminal: +.PP .CS \fBfconfigure\fR stdout -buffering none .CE .PP Open a socket and read lines from it without ever blocking the processing of other events: +.PP .CS set s [socket some.where.com 12345] \fBfconfigure\fR $s -blocking 0 fileevent $s readable "readMe $s" proc readMe chan { - if {[gets $chan line] < 0} { - if {[eof $chan]} { - close $chan - return - } - # Could not read a complete line this time; Tcl's - # internal buffering will hold the partial line for us - # until some more data is available over the socket. - } else { - puts stdout $line - } + if {[gets $chan line] < 0} { + if {[eof $chan]} { + close $chan + return + } + # Could not read a complete line this time; Tcl's + # internal buffering will hold the partial line for us + # until some more data is available over the socket. + } else { + puts stdout $line + } } .CE .PP Read a PPM-format image from a file: +.PP .CS # Open the file and put it into Unix ASCII mode set f [open teapot.ppm] @@ -247,16 +253,16 @@ set f [open teapot.ppm] # Get the header if {[gets $f] ne "P6"} { - error "not a raw\-bits PPM" + error "not a raw\-bits PPM" } # Read lines until we have got non-comment lines # that supply us with three decimal values. set words {} while {[llength $words] < 3} { - gets $f line - if {[string match "#*" $line]} continue - lappend words {expand}[join [scan $line %d%d%d]] + gets $f line + if {[string match "#*" $line]} continue + lappend words {*}[join [scan $line %d%d%d]] } # Those words supply the size of the image and its @@ -271,12 +277,13 @@ set data [read $f $numDataBytes] close $f .CE - .SH "SEE ALSO" close(n), flush(n), gets(n), open(n), puts(n), read(n), socket(n), Tcl_StandardChannels(3) - .SH KEYWORDS blocking, buffering, carriage return, end of line, flushing, linemode, newline, nonblocking, platform, translation, encoding, filter, byte array, binary +'\" Local Variables: +'\" mode: nroff +'\" End: |