[unix-history] / .ref-BSD-3 / usr / man / man2 / vwrite.2

.UC
.TH VWRITE 2
.SH NAME
vwrite \- write (virtually) to file
.SH SYNOPSIS
\fBvwrite(filedes, buffer, nbytes)\fR
.br
\fBchar *buffer;\fR
.SH DESCRIPTION
The
.I vwrite
system call is used in conjunction with
.I vread
to perform efficient updating of large files.
After a call to
.I vread
and updating of the data in the buffer which was given to
.I vread,
a
.I vwrite
of the same buffer to the same
.I filedes
at the same offset in the file
will cause data which has been modified since it was
.I vread
from (or
.I vwritten
to) the file to be returned to the file.
.SH SEE ALSO
vread(2)
.SH DIAGNOSTICS
Returns \-1 on error: bad descriptor, buffer address, count or alignment
as well as on physical I/O errors.
.SH BUGS
The result of
.I vwrite
is defined only when no other
.I vread's
have occured on
.I buffer
since the one matching the
.I vwrite.
Commit	Line	Data
55641529 BJ	1	.UC
	2	.TH VWRITE 2
	3	.SH NAME
	4	vwrite \- write (virtually) to file
	5	.SH SYNOPSIS
	6	\fBvwrite(filedes, buffer, nbytes)\fR
	7	.br
	8	\fBchar *buffer;\fR
	9	.SH DESCRIPTION
	10	The
	11	.I vwrite
	12	system call is used in conjunction with
	13	.I vread
	14	to perform efficient updating of large files.
	15	After a call to
	16	.I vread
	17	and updating of the data in the buffer which was given to
	18	.I vread,
	19	a
	20	.I vwrite
	21	of the same buffer to the same
	22	.I filedes
	23	at the same offset in the file
	24	will cause data which has been modified since it was
	25	.I vread
	26	from (or
	27	.I vwritten
	28	to) the file to be returned to the file.
	29	.SH SEE ALSO
	30	vread(2)
	31	.SH DIAGNOSTICS
	32	Returns \-1 on error: bad descriptor, buffer address, count or alignment
	33	as well as on physical I/O errors.
	34	.SH BUGS
	35	The result of
	36	.I vwrite
	37	is defined only when no other
	38	.I vread's
	39	have occured on
	40	.I buffer
	41	since the one matching the
	42	.I vwrite.