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.Dd $Mdocdate: June 5 2013 $
.Dt GETC 3
.Os
.Sh NAME
.Nm fgetc ,
.Nm getc ,
.Nm getchar ,
.Nm getw
.Nd get next character or word from input stream
.Sh SYNOPSIS
.In stdio.h
.Ft int
.Fn fgetc "FILE *stream"
.Ft int
.Fn getc "FILE *stream"
.Ft int
.Fn getchar "void"
.Ft int
.Fn getw "FILE *stream"
.Sh DESCRIPTION
The
.Fn fgetc
function obtains the next input character (if present) from the stream
pointed at by
.Fa stream ,
or the next character pushed back on the stream via
.Xr ungetc 3 .
.Pp
The
.Fn getc
function acts essentially identically to
.Fn fgetc ,
but is a macro that expands in-line.
.Pp
The
.Fn getchar
function is equivalent to
.Fn getc
with the argument
.Em stdin .
.Pp
The
.Fn getw
function obtains the next
.Li int
(if present)
from the stream pointed at by
.Fa stream .
.Sh RETURN VALUES
If successful, these routines return the next requested object from the
.Fa stream .
If the stream is at end-of-file or a read error occurs, the routines return
.Dv EOF .
The routines
.Xr feof 3
and
.Xr ferror 3
must be used to distinguish between end-of-file and error.
If an error occurs, the global variable
.Va errno
is set to indicate the error.
The end-of-file condition is remembered, even on a terminal, and all
subsequent attempts to read will return
.Dv EOF
until the condition is cleared with
.Xr clearerr 3 .
.Sh SEE ALSO
.Xr ferror 3 ,
.Xr fopen 3 ,
.Xr fread 3 ,
.Xr putc 3 ,
.Xr ungetc 3
.Sh STANDARDS
The
.Fn fgetc ,
.Fn getc ,
and
.Fn getchar
functions conform to
.St -ansiC .
.Sh HISTORY
The
.Fn getc
and
.Fn getw
functions first appeared in
.At v1 ;
.Fn getchar
in
.At v2 ;
and
.Fn fgetc
in
.At v7 .
.Sh AUTHORS
.An Dennis Ritchie
originally implemented
.Fn getc
and
.Fn getw
in PDP-11 assembler.
.Sh BUGS
Since
.Dv EOF
is a valid integer value,
.Xr feof 3
and
.Xr ferror 3
must be used to check for failure after calling
.Fn getw .
.Pp
Since the size and byte order of an
.Vt int
may vary from one machine to another,
.Fn getw
is not recommended for portable applications.