seek(n) Tcl Built-In Commands seek(n)_________________________________________________________________NAMEseek - Change the access position for an open channel
SYNOPSISseek channelId offset ?origin?
_________________________________________________________________DESCRIPTION
Changes the current access position for channelId. Chan-
nelId must be a channel identifier such as returned from a
previous invocation of open or socket. The offset and
origin arguments specify the position at which the next
read or write will occur for channelId. Offset must be an
integer (which may be negative) and origin must be one of
the following:
start The new access position will be offset bytes
from the start of the underlying file or device.
current The new access position will be offset bytes
from the current access position; a negative
offset moves the access position backwards in
the underlying file or device.
end The new access position will be offset bytes
from the end of the file or device. A negative
offset places the access position before the end
of file, and a positive offset places the access
position after the end of file.
The origin argument defaults to start.
The command flushes all buffered output for the channel
before the command 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 under-
lying file or device does not support seeking.
KEYWORDS
access position, file, seekTcl 7.5 1
