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 * and/or 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 <<getchar_unlocked>>---non-thread-safe version of getchar (macro)
21
22 INDEX
23 getchar_unlocked
24 INDEX
25 _getchar_unlocked_r
26
27 SYNOPSIS
28 #include <stdio.h>
29 int getchar_unlocked(void);
30
31 #include <stdio.h>
32 int _getchar_unlocked_r(struct _reent *<[ptr]>);
33
34 DESCRIPTION
35 <<getchar_unlocked>> is a non-thread-safe version of <<getchar>>
36 declared in <<stdio.h>>. <<getchar_unlocked>> may only safely be used
37 within a scope protected by flockfile() (or ftrylockfile()) and
38 funlockfile(). These functions may safely be used in a multi-threaded
39 program if and only if they are called while the invoking thread owns
40 the ( FILE *) object, as is the case after a successful call to the
41 flockfile() or ftrylockfile() functions. If threads are disabled,
42 then <<getchar_unlocked>> is equivalent to <<getchar>>.
43
44 The <<_getchar_unlocked_r>> function is simply the reentrant version of
45 <<getchar_unlocked>> which passes an addtional reentrancy structure pointer
46 argument: <[ptr]>.
47
48 RETURNS
49 See <<getchar>>.
50
51 PORTABILITY
52 POSIX 1003.1 requires <<getchar_unlocked>>. <<getchar_unlocked>> may
53 be implemented as a macro.
54
55 Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
56 <<lseek>>, <<read>>, <<sbrk>>, <<write>>. */
57
58 #if defined(LIBC_SCCS) && !defined(lint)
59 static char sccsid[] = "%W% (Berkeley) %G%";
60 #endif /* LIBC_SCCS and not lint */
61
62 /*
63 * A subroutine version of the macro getchar_unlocked.
64 */
65
66 #define _DEFAULT_SOURCE
67 #include <_ansi.h>
68 #include <stdio.h>
69
70 #undef getchar_unlocked
71
72 int
getchar_unlocked(void)73 getchar_unlocked (void)
74 {
75 /* CHECK_INIT is called (eventually) by __srefill_r. */
76
77 return getc_unlocked ( stdin );
78 }
79
