V3/man/man3/getc.3

.pa 1
.he 'GETC, GETW, FOPEN (III)'3/15/72'GETC, GETW, FOPEN (III)'
.ti 0
NAME		getw, getc, fopen  --  buffered input
.sp
.ti 0
SYNOPSIS	mov	$filename,r0
.br
jsr	r5,fopen; iobuf

jsr	r5,getc; iobuf
.br
(character in r0)

jsr	r5,getw; iobuf
.br
(word in r0)
.sp
.ti 0
DESCRIPTION	These routines are used to provide a buffered input
facility.
iobuf_____ is the address of a 518(10) byte buffer area whose
contents are maintained by these routines.  Its format is:
.sp
.nf
ioptr:	.=.+2		/ file descriptor
	.=.+2		/ characters left in buffer
	.=.+2		/ ptr to next character
	.=.+512.	/ the buffer
.sp
.fi
fopen_____ may be called initially to open the file.  On return,
the error bit (c-bit) is set if the open failed.
If fopen_____ is never called, get___ will read from the standard
input file.
.sp
getc____ returns the next byte from the file in r0.  The
error bit is set on end of file or a read error.
.sp
getw____ returns the next word in r0.  getc____ and getw____
may be used alternately; there are no odd/even
problems.
.sp
iobuf_____ must be provided by the user; it must be on a word boundary.

To reuse the same buffer for another file, it is sufficient
to close the original file and call fopen_____ again.
.sp
.ti 0
FILES		kept in /lib/liba.a
.sp
.ti 0
SEE ALSO	open(II), read(II), putc(III)
.sp
.ti 0
DIAGNOSTICS	c-bit set on EOF or error
.sp
.ti 0
BUGS		--