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OpenDarwin 7.2.1 - man page for puts (opendarwin section n)

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puts(n) 			      Tcl Built-In Commands				  puts(n)

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NAME
       puts - Write to a channel

SYNOPSIS
       puts ?-nonewline? ?channelId? string
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DESCRIPTION
       Writes the characters given by string to the channel given by channelId.

       ChannelId must be an identifier for an open channel such as a Tcl standard channel (stdout |
       or stderr), the return value from an invocation of open or socket,  or  the  result  of	a |
       channel	creation  command  provided by a Tcl extension. The channel must have been opened |
       for output.

       If no channelId is specified then it defaults to stdout. Puts normally outputs  a  newline
       character  after  string,  but this feature may be suppressed by specifying the -nonewline
       switch.

       Newline characters in the output are translated by puts to  platform-specific  end-of-line
       sequences  according  to the current value of the -translation option for the channel (for
       example, on PCs newlines are normally replaced  with  carriage-return-linefeed  sequences;
       on  Macintoshes newlines are normally replaced with carriage-returns).  See the fconfigure
       manual entry for a discussion on ways in which fconfigure will alter output.

       Tcl buffers output internally, so characters written with puts 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 flush command.

       When the output buffer fills up, the puts  command  will  normally  block  until  all  the
       buffered  data  has  been accepted for output by the operating system.  If channelId is in
       nonblocking mode then the puts 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 back-
       ground 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 fileevent command (don't invoke puts unless you have
       recently been notified via a file event that the channel is ready for more output data).

SEE ALSO
       file(n), fileevent(n), Tcl_StandardChannels(3)

KEYWORDS
       channel, newline, output, write

Tcl					       7.5					  puts(n)
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