[unix-history] / usr / src / lib / libc / stdio / fseek.3

.\"	@(#)fseek.3	6.4 (Berkeley) %G%
.\"
.TH FSEEK 3S  ""
.AT 3
.SH NAME
fseek, ftell, rewind \- reposition a stream
.SH SYNOPSIS
.B #include <stdio.h>
.PP
.B fseek(stream, offset, ptrname)
.br
.SM
.B FILE
.B *stream;
.br
.B long offset;
.PP
.B long ftell(stream)
.br
.SM
.B FILE
.B *stream;
.PP
.B rewind(stream)
.SH DESCRIPTION
.I Fseek
sets the position of the next input or output
operation on the
.IR stream .
The new position is at the signed distance
.I offset
bytes
from the beginning, the current position, or the end of the file,
according as 
.I ptrname
has the value 0, 1, or 2.
.PP
.I Fseek
undoes any effects of
.IR  ungetc (3S).
.PP
.I Ftell
returns the current value of the offset relative to the beginning
of the file associated with the named
.IR stream .
It is measured in bytes on UNIX;
on some other systems it is a magic cookie,
and the only foolproof way to obtain an 
.I offset
for
.IR fseek .
.PP
.IR Rewind ( stream )
is equivalent to
.IR fseek ( stream ,
0L, L_SET).
.SH "SEE ALSO"
lseek(2),
fopen(3S)
.SH DIAGNOSTICS
.I Fseek
returns \-1 for improper seeks, otherwise zero.
Commit	Line	Data
bb0a128d	1	.\" @(#)fseek.3 6.4 (Berkeley) %G%
4f278f49	2	.\"
0431d494	3	.TH FSEEK 3S ""
4f278f49 KM	4	.AT 3
	5	.SH NAME
	6	fseek, ftell, rewind \- reposition a stream
	7	.SH SYNOPSIS
	8	.B #include <stdio.h>
	9	.PP
edb5b917	10	.B fseek(stream, offset, ptrname)
4f278f49 KM	11	.br
	12	.SM
	13	.B FILE
	14	.B *stream;
	15	.br
	16	.B long offset;
	17	.PP
	18	.B long ftell(stream)
	19	.br
	20	.SM
	21	.B FILE
	22	.B *stream;
	23	.PP
	24	.B rewind(stream)
	25	.SH DESCRIPTION
	26	.I Fseek
	27	sets the position of the next input or output
	28	operation on the
	29	.IR stream .
	30	The new position is at the signed distance
	31	.I offset
	32	bytes
	33	from the beginning, the current position, or the end of the file,
	34	according as
	35	.I ptrname
	36	has the value 0, 1, or 2.
	37	.PP
	38	.I Fseek
	39	undoes any effects of
11d86b43	40	.IR ungetc (3S).
4f278f49 KM	41	.PP
	42	.I Ftell
	43	returns the current value of the offset relative to the beginning
	44	of the file associated with the named
	45	.IR stream .
	46	It is measured in bytes on UNIX;
	47	on some other systems it is a magic cookie,
	48	and the only foolproof way to obtain an
	49	.I offset
	50	for
	51	.IR fseek .
	52	.PP
11d86b43	53	.IR Rewind ( stream )
4f278f49	54	is equivalent to
11d86b43	55	.IR fseek ( stream ,
bb0a128d	56	0L, L_SET).
4f278f49 KM	57	.SH "SEE ALSO"
4f278f49 KM	58	lseek(2),
11d86b43	59	fopen(3S)
edb5b917 JL	60	.SH DIAGNOSTICS
	61	.I Fseek
	62	returns \-1 for improper seeks, otherwise zero.