FXPSEEK Name
FXPSEEK
Author
Craig B. Markwardt, NASA/GSFC Code 662, Greenbelt, MD 20770
craigm@lheamail.gsfc.nasa.gov
UPDATED VERSIONs can be found on my WEB PAGE:
http://cow.physics.wisc.edu/~craigm/idl/idl.html
Purpose
Internal routine to perform seek on a Unix Pipe.
Description
See the following procedures for appropriate documentation.
FXGOPEN - open resource
FXGCLOSE - close resource
FXGREAD - read from resource
FXGWRITE - write to resource
FXGSEEK - seek on resource (i.e., perform POINT_LUN)
FXGFILTERED - determine if resource is a normal file.
Parameters
unit - the pipe LUN. If positive, then the file pointer is moved
to POSITION in the pipe output. [ In reality the file
pointer is moved in the cache file. ] If negative, then
the file pointer of the file unit -LUN is returned in
POSITION.
position - the file pointer, either passed or returned as defined
by UNIT.
Side Effects
The file pointer may be updated.
Actual file accesses are postponed until needed (ie, when FXPREAD
is called). Modification History
Changed copyright notice, 21 Sep 2000, CM