XPAChanges(7) Changes For Users from XPA 1.0 and 2.0


This document describes changes that will affect users who migrate from XPA 1.0 to XPA 2.0.


There have been a few changes that affect users who upgrade XPA from version 1.0 to version 2.0. These changes are detailed below.
  • XPA commands no longer have a resolver routine (this is open to negotiations, but we decided the idea was dumb). For the SAOtng program, this means that you must explicitly specify the access point, i.e.,:

      cat foo.fits | xpaset SAOtng fits

    instead of:

      cat foo.fits | xpaset SAOtng
  • By default, xpaset, xpaget, etc. now wait for the server callback to complete; i.e., the old -W is implied (and the switch is ignored). This allows support for better error handling. If you want xpaset, etc. to return before the callback is complete, use -n switch:

      echo "file foo.fits" | xpaset -n SAOtng
  • The old -w switch in xpaset and xpaget is no longer necessary (and is ignored), since you can have more than one process communicating with an xpa access point at one time.
  • The new -p switch on xpaset means you need not read from stdout:

      xpaset -p SAOtng colormap I8

    will send the paramlist to the SAOtng callback without reading from stdin.