DragonFly On-Line Manual Pages

FPUTS(3)              DragonFly Library Functions Manual              FPUTS(3)

NAME
     fputs, fputs_unlocked, puts - output a line to a stream

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <stdio.h>

     int
     fputs(const char * restrict str, FILE * restrict stream);

     int
     fputs_unlocked(const char *str, FILE *stream);

     int
     puts(const char *str);

DESCRIPTION
     The function fputs() writes the string pointed to by str to the stream
     pointed to by stream.

     The fputs_unlocked() function is equivalent to fputs(), except that the
     caller is responsible for locking the stream with flockfile(3) before
     calling it.  This function may be used to avoid the overhead of locking
     the stream and to prevent races when multiple threads are operating on
     the same stream.

     The function puts() writes the string str, and a terminating newline
     character, to the stream stdout.

RETURN VALUES
     The functions fputs() and puts() return a nonnegative integer on success
     and EOF on error.

ERRORS
     [EBADF]            The stream argument is not a writable stream.

     The functions fputs() and puts() may also fail and set errno for any of
     the errors specified for the routines write(2).

SEE ALSO
     ferror(3), fputws(3), putc(3), stdio(3)

STANDARDS
     The functions fputs() and puts() conform to ISO/IEC 9899:1990
     ("ISO C90").

DragonFly 5.9-DEVELOPMENT      November 22, 2020     DragonFly 5.9-DEVELOPMENT
puts(n)                      Tcl Built-In Commands                     puts(n)

______________________________________________________________________________

NAME
       puts - Write to a channel

SYNOPSIS
       puts ?-nonewline? ?channelId? string
______________________________________________________________________________

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.  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
       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 fileevent
       command (do not invoke puts unless you have recently been notified via
       a file event that the channel is ready for more output data).

EXAMPLES
       Write a short message to the console (or wherever stdout is directed):

              puts "Hello, World!"

       Print a message in several parts:

              puts -nonewline "Hello, "
              puts "World!"

       Print a message to the standard error channel:

              puts stderr "Hello, World!"

       Append a log message to a file:

              set chan [open my.log a]
              set timestamp [clock format [clock seconds]]
              puts $chan "$timestamp - Hello, World!"
              close $chan

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

KEYWORDS
       channel, newline, output, write

Tcl                                   7.5                              puts(n)