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Diffstat (limited to 'doc/puts.n')
| -rw-r--r-- | doc/puts.n | 88 |
1 files changed, 3 insertions, 85 deletions
@@ -16,92 +16,10 @@ puts \- Write to a channel .BE .SH DESCRIPTION .PP -Writes the characters given by \fIstring\fR to the channel given -by \fIchannelId\fR. -.PP -\fIChannelId\fR must be an identifier for an open channel such as a -Tcl standard channel (\fBstdout\fR or \fBstderr\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 output. -.PP -If no \fIchannelId\fR is specified then it defaults to -\fBstdout\fR. \fBPuts\fR normally outputs a newline character after -\fIstring\fR, but this feature may be suppressed by specifying the -\fB\-nonewline\fR switch. -.PP -Newline characters in the output are translated by \fBputs\fR to -platform-specific end-of-line sequences according to the current -value of the \fB\-translation\fR option for the channel (for example, -on PCs newlines are normally replaced with carriage-return-linefeed -sequences. -See the \fBfconfigure\fR manual entry for a discussion on ways in -which \fBfconfigure\fR will alter output. -.PP -Tcl buffers output internally, so characters written with \fBputs\fR -may not appear immediately on the output file or device; Tcl will -normally delay output until the buffer is full or the channel is -closed. -You can force output to appear immediately with the \fBflush\fR -command. -.PP -When the output buffer fills up, the \fBputs\fR command will normally -block until all the buffered data has been accepted for output by the -operating system. -If \fIchannelId\fR is in nonblocking mode then the \fBputs\fR command -will not block even if the operating system cannot accept the data. -Instead, Tcl continues to buffer the data and writes it in the -background as fast as the underlying file or device can accept it. -The application must use the Tcl event loop for nonblocking output -to work; otherwise Tcl never finds out that the file or device is -ready for more output data. -It is possible for an arbitrarily large amount of data to be -buffered for a channel in nonblocking mode, which could consume a -large amount of memory. -To avoid wasting memory, nonblocking I/O should normally -be used in an event-driven fashion with the \fBfileevent\fR command -(do not invoke \fBputs\fR unless you have recently been notified -via a file event that the channel is ready for more output data). -.SH "ENCODING ERRORS" -.PP -Encoding errors may exist, if the encoding profile \fBstrict\fR is used. -\fBputs\fR writes out data until an encoding error occurs and fails with -POSIX error code \fBEILSEQ\fR. - -.SH EXAMPLES -.PP -Write a short message to the console (or wherever \fBstdout\fR is -directed): -.PP -.CS -\fBputs\fR "Hello, World!" -.CE -.PP -Print a message in several parts: -.PP -.CS -\fBputs\fR -nonewline "Hello, " -\fBputs\fR "World!" -.CE -.PP -Print a message to the standard error channel: -.PP -.CS -\fBputs\fR stderr "Hello, World!" -.CE -.PP -Append a log message to a file: -.PP -.CS -set chan [open my.log a] -set timestamp [clock format [clock seconds]] -\fBputs\fR $chan "$timestamp - Hello, World!" -close $chan -.CE +The \fBputs\fR command has been superceded by the \fBchan puts\fR +command which supports the same syntax and options. .SH "SEE ALSO" -file(n), fileevent(n), Tcl_StandardChannels(3) -.SH KEYWORDS -channel, newline, output, write +chan(n) '\" Local Variables: '\" mode: nroff '\" fill-column: 78 |