3.15. Avaliable Functions

guess_display

this function tries to guess a valid X-display-string suitable for a DISPLAY-environment variable.

Consider using the forward_x11 process flag instead - its designed to be easier and more robust!

The guess is based on the current value of the managers DISPLAY environment variable. It has no arguments.

When the process is to be started on the same host as the manager run’s on, %(guess_display) will equal to %(env DISPLAY). when the process is to be started on a remote host, and the managers local %(env DISPLAY) contains no host-part the manager-ip address (as seen from the remote host) is prepended. if there is a host-part the DISPLAY environment variable it is passed unmodified. example usage:

process pyXpferd
node: guihost
environment: PYTHONPATH=%(LN_PYTHONPATH), DISPLAY=%(guess_display)
pass_environment: USER, HOME, XAUTH
command: /usr/bin/python %(ln_base)/library/tests/python/slow_subscribe.py 500

ifeq

This function checks for equality (python ==) of the two parameters specified first. In case they are equal, the third parameter is returned, else th fourth one.

Example:

%(ifeq "3.0", "3", "equal", "not equal")

Note that this will get replaced by not equal, as a string-comparison is done on the parameters.