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 <<getc>>---read a character (macro)
21
22 INDEX
23 getc
24 INDEX
25 _getc_r
26
27 SYNOPSIS
28 #include <stdio.h>
29 int getc(FILE *<[fp]>);
30
31 #include <stdio.h>
32 int getc( FILE *<[fp]>);
33
34 DESCRIPTION
35 <<getc>> is a macro, defined in <<stdio.h>>. You can use <<getc>>
36 to get the next single character from the file or stream
37 identified by <[fp]>. As a side effect, <<getc>> advances the file's
38 current position indicator.
39
40 For a subroutine version of this macro, see <<fgetc>>.
41
42 The <<_getc_r>> function is simply the reentrant version of <<getc>>
43 which passes an additional reentrancy structure pointer argument: <[ptr]>.
44
45 RETURNS
46 The next character (read as an <<unsigned char>>, and cast to
47 <<int>>), unless there is no more data, or the host system reports a
48 read error; in either of these situations, <<getc>> returns <<EOF>>.
49
50 You can distinguish the two situations that cause an <<EOF>> result by
51 using the <<ferror>> and <<feof>> functions.
52
53 PORTABILITY
54 ANSI C requires <<getc>>; it suggests, but does not require, that
55 <<getc>> be implemented as a macro. The standard explicitly permits
56 macro implementations of <<getc>> to use the argument more than once;
57 therefore, in a portable program, you should not use an expression
58 with side effects as the <<getc>> argument.
59
60 Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
61 <<lseek>>, <<read>>, <<sbrk>>, <<write>>.
62 */
63
64 #if defined(LIBC_SCCS) && !defined(lint)
65 static char sccsid[] = "%W% (Berkeley) %G%";
66 #endif /* LIBC_SCCS and not lint */
67
68 #define _DEFAULT_SOURCE
69 #include <_ansi.h>
70 #include <stdio.h>
71 #include "local.h"
72
73 /*
74 * A subroutine version of the macro getc.
75 */
76
77 #undef getc
78
79 int
getc(register FILE * fp)80 getc (
81 register FILE *fp)
82 {
83 int result;
84 CHECK_INIT (ptr, fp);
85 _newlib_flockfile_start (fp);
86 result = _sgetc ( fp);
87 _newlib_flockfile_end (fp);
88 return result;
89 }
90
