xref: /netbsd-src/lib/libc/stdio/getc.3 (revision 1f2744e6e4915c9da2a3f980279398c4cf7d5e6d)
1.\"	$NetBSD: getc.3,v 1.3 1995/02/02 01:15:45 jtc Exp $
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3.\" Copyright (c) 1990, 1991, 1993
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6.\" This code is derived from software contributed to Berkeley by
7.\" Chris Torek and the American National Standards Committee X3,
8.\" on Information Processing Systems.
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38.\"     @(#)getc.3	8.1 (Berkeley) 6/4/93
39.\"
40.Dd June 4, 1993
41.Dt GETC 3
42.Os
43.Sh NAME
44.Nm fgetc ,
45.Nm getc ,
46.Nm getchar ,
47.Nm getw
48.Nd get next character or word from input stream
49.Sh SYNOPSIS
50.Fd #include <stdio.h>
51.Ft int
52.Fn fgetc "FILE *stream"
53.Ft int
54.Fn getc "FILE *stream"
55.Ft int
56.Fn getchar
57.Ft int
58.Fn getw "FILE *stream"
59.Sh DESCRIPTION
60The
61.Fn fgetc
62function
63obtains the next input character (if present) from the stream pointed at by
64.Fa stream ,
65or the next character pushed back on the stream via
66.Xr ungetc .
67.Pp
68The
69.Fn getc
70function
71acts essentially identically to
72.Fn fgetc ,
73but is a macro that expands in-line.
74.Pp
75The
76.Fn getchar
77function
78is equivalent to:
79getc with the argument stdin.
80.Pp
81The
82.Fn getw
83function
84obtains the next
85.Em int
86(if present)
87from the stream pointed at by
88.Fa stream .
89.Sh RETURN VALUES
90If successful, these routines return the next requested object
91from the
92.Fa stream .
93If the stream is at end-of-file or a read error occurs,
94the routines return
95.Dv EOF .
96The routines
97.Xr feof 3
98and
99.Xr ferror 3
100must be used to distinguish between end-of-file and error.
101If an error occurs, the global variable
102.Va errno
103is set to indicate the error.
104The end-of-file condition is remembered, even on a terminal, and all
105subsequent attempts to read will return
106.Dv EOF
107until the condition is cleared with
108.Xr clearerr .
109.Sh SEE ALSO
110.Xr ferror 3 ,
111.Xr fread 3 ,
112.Xr fopen 3 ,
113.Xr putc 3 ,
114.Xr ungetc 3
115.Sh STANDARDS
116The
117.Fn fgetc ,
118.Fn getc
119and
120.Fn getchar
121functions
122conform to
123.St -ansiC .
124.Sh BUGS
125Since
126.Dv EOF
127is a valid integer value,
128.Xr feof
129and
130.Xr ferror
131must be used to check for failure after calling
132.Fn getw .
133The size and byte order of an
134.Em int
135varies from one machine to another, and
136.Fn getw
137is not recommended for portable applications.
138.Pp
139