.\" $NetBSD: getc.3,v 1.12.100.1 2019/09/05 08:19:40 martin Exp $ .\" .\" Copyright (c) 1990, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" This code is derived from software contributed to Berkeley by .\" Chris Torek and the American National Standards Committee X3, .\" on Information Processing Systems. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)getc.3 8.1 (Berkeley) 6/4/93 .\" .Dd September 2, 2019 .Dt GETC 3 .Os .Sh NAME .Nm fgetc , .Nm getc , .Nm getchar , .Nm getc_unlocked , .Nm getchar_unlocked , .Nm getw .Nd get next character or word from input stream .Sh LIBRARY .Lb libc .Sh SYNOPSIS .In stdio.h .Ft int .Fn fgetc "FILE *stream" .Ft int .Fn getc "FILE *stream" .Ft int .Fn getchar .Ft int .Fn getc_unlocked "FILE *stream" .Ft int .Fn getchar_unlocked .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: getc with the argument stdin. .Pp The .Fn getc_unlocked and .Fn getchar_unlocked functions provide functionality identical to that of .Fn getc and .Fn getchar , respectively, but do not perform implicit locking of the streams they operate on. In multi-threaded programs they may be used .Em only within a scope in which the stream has been successfully locked by the calling thread using either .Xr flockfile 3 or .Xr ftrylockfile 3 , and may later be released using .Xr funlockfile 3 . .Pp The .Fn getw function obtains the next .Em 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 flockfile 3 , .Xr fopen 3 , .Xr fread 3 , .Xr ftrylockfile 3 , .Xr funlockfile 3 , .Xr putc 3 , .Xr ungetc 3 .Sh STANDARDS The .Fn fgetc , .Fn getc and .Fn getchar functions conform to .St -ansiC . The .Fn getc_unlocked and .Fn getchar_unlocked functions conform to .St -p1003.1-96 . .Sh HISTORY The .Fn getc and .Fn getw functions appeared in .At v1 . .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 . The size and byte order of an .Em int varies from one machine to another, and .Fn getw is not recommended for portable applications.