toolchain/gcc/newlib/libc/stdio/putc_u.c

   1 /*
   2  * Copyright (c) 1990 The Regents of the University of California.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms are permitted
   6  * provided that the above copyright notice and this paragraph are
   7  * duplicated in all such forms and that any documentation,
   8  * advertising materials, and other materials related to such
   9  * distribution and use acknowledge that the software was developed
  10  * by the University of California, Berkeley.  The name of the
  11  * University may not be used to endorse or promote products derived
  12  * from this software without specific prior written permission.
  13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  16  */
  17
  18 /*
  19 FUNCTION
  20 <<putc_unlocked>>---non-thread-safe version of putc (macro)
  21
  22 INDEX
  23         putc_unlocked
  24
  25 POSIX_SYNOPSIS
  26         #include <stdio.h>
  27         int putc_unlocked(int <[ch]>, FILE *<[fp]>);
  28
  29 DESCRIPTION
  30 <<putc_unlocked>> is a non-thread-safe version of <<putc>> declared in
  31 <<stdio.h>>.  <<putc_unlocked>> may only safely be used within a scope
  32 protected by flockfile() (or ftrylockfile()) and funlockfile().  These
  33 functions may safely be used in a multi-threaded program if and only
  34 if they are called while the invoking thread owns the ( FILE *)
  35 object, as is the case after a successful call to the flockfile() or
  36 ftrylockfile() functions.  If threads are disabled, then
  37 <<putc_unlocked>> is equivalent to <<putc>>.
  38
  39 RETURNS
  40 See <<putc>>.
  41
  42 PORTABILITY
  43 POSIX 1003.1 requires <<putc_unlocked>>.  <<putc_unlocked>> may be
  44 implemented as a macro, so arguments should not have side-effects.
  45
  46 Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
  47 <<lseek>>, <<read>>, <<sbrk>>, <<write>>.  */
  48
  49 #if defined(LIBC_SCCS) && !defined(lint)
  50 static char sccsid[] = "%W% (Berkeley) %G%";
  51 #endif /* LIBC_SCCS and not lint */
  52
  53 #include <stdio.h>
  54
  55 /*
  56  * A subroutine version of the macro putc_unlocked.
  57  */
  58
  59 #undef putc_unlocked
  60
  61 int
  62 putc_unlocked (c, fp)
  63      int c;
  64      register FILE *fp;
  65 {
  66   /* CHECK_INIT is (eventually) called by __swbuf.  */
  67
  68   return __sputc (c, fp);
  69 }