Vortex scripts are specified in the URL to the texis
CGI
program (see below), or as an argument if run from the command line
(here). In either case, the script is first
compiled to an internal form, which is written out to a file with the
same name and a .vsc
extension.
The P-code (.vsc
) file is run on each invocation, which is
much faster than re-interpreting the script every time. Subsequent
invocations will automatically recompile the script if its source is
changed. Any errors encountered during compile or execution are
printed out, with the script name and line number if applicable. The
errors are also logged to the vortex.log
file (see
here for the format). These errors may be trapped
and handled by the script during execution with a putmsg
function.
Script execution starts with the function given in the URL. If no
function is specified in the URL, then the value of the CGI variable
cmd
(section 1.4.1) is used. If neither is given or
is an invalid or PRIVATE
/EXPORT
function, execution
defaults to the main
function.