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fputc(3C)		 Standard C Library Functions		     fputc(3C)

NAME
       fputc,  putc,  putc_unlocked,  putchar,	putchar_unlocked, putw - put a
       byte on a stream

SYNOPSIS
       #include	<stdio.h>

       int fputc(int c,	FILE *stream);

       int putc(int c, FILE *stream);

       int putc_unlocked(int c,	FILE *stream);

       int putchar(int c);

       int putchar_unlocked(int	c);

       int putw(int w, FILE *stream);

DESCRIPTION
       The fputc() function writes the byte specified by c  (converted	to  an
       unsigned	 char) to the output stream pointed to by stream, at the posi-
       tion indicated by the associated	file-position indicator	for the	stream
       (if  defined),  and  advances  the indicator appropriately. If the file
       cannot support positioning requests, or if the stream was  opened  with
       append mode, the	byte is	appended to the	output stream.

       The  st_ctime and st_mtime fields of the	file will be marked for	update
       between the successful execution	of fputc()  and	 the  next  successful
       completion  of a	call to	fflush(3C) or fclose(3C) on the	same stream or
       a call to exit(3C) or abort(3C).

       The putc() routine behaves like fputc(),	except that it is  implemented
       as a macro. It runs faster than fputc(),	but it takes up	more space per
       invocation and its name cannot be passed	as an argument to  a  function
       call.

       The  call  putchar(c)  is  equivalent to	putc(c,	stdout). The putchar()
       routine is implemented as a macro.

       The putc_unlocked() and putchar_unlocked()  routines  are  variants  of
       putc() and putchar(), respectively, that	do not lock the	stream.	 It is
       the caller's responsibility to acquire the stream lock  before  calling
       these routines and releasing the	lock afterwards; see flockfile(3C) and
       stdio(3C). These	routines are implemented as macros.

       The putw() function writes the word (that is, type int) w to the	output
       stream (at the position at which	the file offset, if defined, is	point-
       ing). The size of a word	is the size of a type int and varies from  ma-
       chine  to machine.  The putw() function neither assumes nor causes spe-
       cial alignment in the file.

       The st_ctime and	st_mtime fields	of the file will be marked for	update
       between the successful execution	of putw() and the next successful com-
       pletion of a call to fflush(3C) or fclose(3C) on	the same stream	 or  a
       call to exit(3C)	or abort(3C).

RETURN VALUES
       Upon   successful   completion,	 fputc(),   putc(),   putc_unlocked(),
       putchar(), and putchar_unlocked() return	the value  that	 was  written.
       Otherwise,  these  functions  return  EOF,  the error indicator for the
       stream is set, and errno	is set to indicate the error.

       Upon successful completion, putw() returns 0. Otherwise,	it  returns  a
       non-zero	value, sets the	error indicator	for the	associated stream, and
       sets errno to indicate the error.

       An unsuccessful completion will occur, for example, if the file associ-
       ated  with  stream is not open for writing or if	the output file	cannot
       grow.

ERRORS
       The fputc(), putc(),  putc_unlocked(),  putchar(),  putchar_unlocked(),
       and  putw()  functions  will fail if either the stream is unbuffered or
       the stream's buffer needs to be flushed,	and:

       EAGAIN	       The O_NONBLOCK flag is set for the file descriptor  un-
		       derlying	stream and the process would be	delayed	in the
		       write operation.

       EBADF	       The file	descriptor underlying stream is	 not  a	 valid
		       file descriptor open for	writing.

       EFBIG	       An attempt was made to write to a file that exceeds the
		       maximum file size  or the process' file size limit.

       EFBIG	       The file	is a regular file and an attempt was  made  to
		       write at	or beyond the offset maximum.

       EINTR	       The  write  operation was terminated due	to the receipt
		       of a signal, and	no data	was transferred.

       EIO	       A physical I/O error has	occurred, or  the process is a
		       member  of  a  background  process  group attempting to
		       write to	its controlling	terminal, TOSTOP is  set,  the
		       process	is  neither  ignoring nor blocking SIGTTOU and
		       the process group of the	process	is orphaned. This  er-
		       ror may also be returned	under implementation-dependent
		       conditions.

       ENOSPC	       There was no free space remaining on  the  device  con-
		       taining the file.

       EPIPE	       An  attempt  is made to write to	a pipe or FIFO that is
		       not open	for reading by any process. A  SIGPIPE	signal
		       will also be sent to the	calling	thread.

       The  fputc(),  putc(),  putc_unlocked(),	putchar(), putchar_unlocked(),
       and putw() functions may	fail if:

       ENOMEM	       Insufficient storage space is available.

       ENXIO	       A request was made of a non-existent device, or the re-
		       quest was outside the capabilities of the device.

USAGE
       Functions   exist  for  the  putc(),  putc_unlocked(),  putchar(),  and
       putchar_unlocked() macros. To get the function  form,  the  macro  name
       must be undefined (for example, #undef putc).

       When  the macro forms are used, putc() and putc_unlocked() evaluate the
       stream argument more than once. In particular, putc(c, *f++); does  not
       work sensibly.  The fputc() function should be used instead when	evalu-
       ating the stream	argument has side effects.

       Because of possible differences in word length and byte ordering, files
       written	using putw() are implementation-dependent, and possibly	cannot
       be read using getw(3C) by a different application or by the same	appli-
       cation running in a different environment.

       The  putw() function is inherently byte stream oriented and is not ten-
       able in the context of either multibyte character streams or wide-char-
       acter streams. Application programmers are encouraged to	use one	of the
       character-based output functions	instead.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |fputc(),	putc(),	 putc_un-  |
       |			     |locked(),	  putchar(),  and  |
       |			     |putchar_unlocked()      are  |
       |			     |Standard.			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |See NOTES	below.		   |
       +-----------------------------+-----------------------------+

SEE ALSO
       getrlimit(2),   ulimit(2)   write(2),  intro(3),	 abort(3C),  exit(3C),
       fclose(3C),   ferror(3C),   fflush(3C),	 flockfile(3C),	  fopen(3UCB),
       printf(3C),  putc(3C),  puts(3C), setbuf(3C), stdio(3C),	attributes(5),
       standards(5)

NOTES
       The fputc(), putc(), putchar(), and putw() routines are MT-Safe in mul-
       tithreaded  applications.   The	putc_unlocked()	and putchar_unlocked()
       routines	are unsafe in multithreaded applications.

SunOS 5.10			  1 Nov	2003			     fputc(3C)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | USAGE | ATTRIBUTES | SEE ALSO | NOTES

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