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-rw-r--r--doc/seek.n19
1 files changed, 13 insertions, 6 deletions
diff --git a/doc/seek.n b/doc/seek.n
index 9214f8e..02c5341 100644
--- a/doc/seek.n
+++ b/doc/seek.n
@@ -14,7 +14,6 @@ seek \- Change the access position for an open channel
.SH SYNOPSIS
\fBseek \fIchannelId offset \fR?\fIorigin\fR?
.BE
-
.SH DESCRIPTION
.PP
Changes the current access position for \fIchannelId\fR.
@@ -30,24 +29,27 @@ for \fIchannelId\fR. \fIOffset\fR must be an integer (which may be
negative) and \fIorigin\fR must be one of the following:
.TP 10
\fBstart\fR
+.
The new access position will be \fIoffset\fR bytes from the start
of the underlying file or device.
.TP 10
\fBcurrent\fR
+.
The new access position will be \fIoffset\fR bytes from the current
access position; a negative \fIoffset\fR moves the access position
backwards in the underlying file or device.
.TP 10
\fBend\fR
+.
The new access position will be \fIoffset\fR bytes from the end of
the file or device. A negative \fIoffset\fR places the access position
before the end of file, and a positive \fIoffset\fR places the access
position after the end of file.
-.LP
+.PP
The \fIorigin\fR argument defaults to \fBstart\fR.
.PP
The command flushes all buffered output for the channel before the command
-returns, even if the channel is in nonblocking mode.
+returns, even if the channel is in non-blocking mode.
It also discards any buffered and unread input.
This command returns an empty string.
An error occurs if this command is applied to channels whose underlying
@@ -57,17 +59,20 @@ Note that \fIoffset\fR values are byte offsets, not character
offsets. Both \fBseek\fR and \fBtell\fR operate in terms of bytes,
not characters, unlike \fBread\fR.
.SH EXAMPLES
+.PP
Read a file twice:
+.PP
.CS
set f [open file.txt]
set data1 [read $f]
\fBseek\fR $f 0
set data2 [read $f]
close $f
-# $data1 == $data2 if the file wasn't updated
+# $data1 eq $data2 if the file wasn't updated
.CE
.PP
Read the last 10 bytes from a file:
+.PP
.CS
set f [open file.data]
# This is guaranteed to work with binary data but
@@ -77,9 +82,11 @@ fconfigure $f -translation binary
set data [read $f 10]
close $f
.CE
-
.SH "SEE ALSO"
file(n), open(n), close(n), gets(n), tell(n), Tcl_StandardChannels(3)
-
.SH KEYWORDS
access position, file, seek
+'\" Local Variables:
+'\" mode: nroff
+'\" fill-column: 78
+'\" End: