[unix-history] / man / man3 / getchr.3

.th GETCHAR III 4/7/73
.sh NAME
getchar \*- read character
.sh SYNOPSIS
.ft B
getchar( )
.br
.ft R
.sh DESCRIPTION
.it Getchar
provides the simplest means of reading characters from
the standard input for C programs.
It returns successive characters until end-of-file,
when it returns ``\\0''.
.s3
Associated with this routine is an external variable
called \fIfin\fR, which is a structure containing
a buffer such as described under \fIgetc\fR (III).
.s3
Normally input via \fIgetchar\fR is unbuffered,
but if the file-descriptor (first) word of
.it fin
is non-zero,
.it getchar
calls
.it getc
with
.it fin
as
argument.
This means that
.s3
	fin = open(...)
.s3
makes
.it getchar
return (buffered) input from
the opened file; also
.s3
	fin = dup(0);
.s3
causes the standard input to be buffered.
.s3
Generally speaking,
.it getchar
should be used only for the simplest applications;
.it getc
is better when there are multiple input files.
.sh "SEE ALSO"
getc (III)
.sh DIAGNOSTICS
Null character returned on EOF or error.
.sh BUGS
\*-1 should be
returned on EOF; null is a legitimate character.
Commit	Line	Data
d7d04d31 KT	1	.th GETCHAR III 4/7/73
	2	.sh NAME
	3	getchar \*- read character
	4	.sh SYNOPSIS
	5	.ft B
	6	getchar( )
	7	.br
	8	.ft R
	9	.sh DESCRIPTION
	10	.it Getchar
	11	provides the simplest means of reading characters from
	12	the standard input for C programs.
	13	It returns successive characters until end-of-file,
	14	when it returns ``\\0''.
	15	.s3
	16	Associated with this routine is an external variable
	17	called \fIfin\fR, which is a structure containing
	18	a buffer such as described under \fIgetc\fR (III).
	19	.s3
	20	Normally input via \fIgetchar\fR is unbuffered,
	21	but if the file-descriptor (first) word of
	22	.it fin
	23	is non-zero,
	24	.it getchar
	25	calls
	26	.it getc
	27	with
	28	.it fin
	29	as
	30	argument.
	31	This means that
	32	.s3
	33	fin = open(...)
	34	.s3
	35	makes
	36	.it getchar
	37	return (buffered) input from
	38	the opened file; also
	39	.s3
	40	fin = dup(0);
	41	.s3
	42	causes the standard input to be buffered.
	43	.s3
	44	Generally speaking,
	45	.it getchar
	46	should be used only for the simplest applications;
	47	.it getc
	48	is better when there are multiple input files.
	49	.sh "SEE ALSO"
	50	getc (III)
	51	.sh DIAGNOSTICS
	52	Null character returned on EOF or error.
	53	.sh BUGS
	54	\*-1 should be
	55	returned on EOF; null is a legitimate character.