xref: /freebsd/lib/libc/stdio/getc.3 (revision e627b39baccd1ec9129690167cf5e6d860509655)
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36.\"     @(#)getc.3	8.1 (Berkeley) 6/4/93
37.\"
38.Dd June 4, 1993
39.Dt GETC 3
40.Os
41.Sh NAME
42.Nm fgetc ,
43.Nm getc ,
44.Nm getchar ,
45.Nm getw
46.Nd get next character or word from input stream
47.Sh SYNOPSIS
48.Fd #include <stdio.h>
49.Ft int
50.Fn fgetc "FILE *stream"
51.Ft int
52.Fn getc "FILE *stream"
53.Ft int
54.Fn getchar
55.Ft int
56.Fn getw "FILE *stream"
57.Sh DESCRIPTION
58The
59.Fn fgetc
60function
61obtains the next input character (if present) from the stream pointed at by
62.Fa stream ,
63or the next character pushed back on the stream via
64.Xr ungetc 3 .
65.Pp
66The
67.Fn getc
68function
69acts essentially identically to
70.Fn fgetc ,
71but is a macro that expands in-line.
72.Pp
73The
74.Fn getchar
75function
76is equivalent to:
77getc with the argument stdin.
78.Pp
79The
80.Fn getw
81function
82obtains the next
83.Em int
84(if present)
85from the stream pointed at by
86.Fa stream .
87.Sh RETURN VALUES
88If successful, these routines return the next requested object
89from the
90.Fa stream .
91If the stream is at end-of-file or a read error occurs,
92the routines return
93.Dv EOF .
94The routines
95.Xr feof 3
96and
97.Xr ferror 3
98must be used to distinguish between end-of-file and error.
99If an error occurs, the global variable
100.Va errno
101is set to indicate the error.
102The end-of-file condition is remembered, even on a terminal, and all
103subsequent attempts to read will return
104.Dv EOF
105until the condition is cleared with
106.Xr clearerr 3 .
107.Sh SEE ALSO
108.Xr ferror 3 ,
109.Xr fread 3 ,
110.Xr fopen 3 ,
111.Xr putc 3 ,
112.Xr ungetc 3
113.Sh STANDARDS
114The
115.Fn fgetc ,
116.Fn getc
117and
118.Fn getchar
119functions
120conform to
121.St -ansiC .
122.Sh BUGS
123Since
124.Dv EOF
125is a valid integer value,
126.Xr feof 3
127and
128.Xr ferror 3
129must be used to check for failure after calling
130.Fn getw .
131The size and byte order of an
132.Em int
133varies from one machine to another, and
134.Fn getw
135is not recommended for portable applications.
136.Pp
137