From the ground up, PSL was designed to be incorporated into a work flow. PSL can be called from the command line. PSL can call other programs or be called by them. Furthermore PSL supports “call backs.” Upon certain events, such as warnings, errors, end of page, end of file, etc., users can write functions to deal with such events. One example would be that when PSL is called by another program, and a warning is issued by PSL, that warning can be sent to the calling program. Or, for just one more example, an e-mail might be sent to a person advising him or her as to what has happened. The famous “lights out” functionality can be achieved with PSL.
“Enterprise Architecture” also implies some “scalability” issues such as described in a previous section. To review here;
- Tables, files and programs have no size limits,
- Tables can contain files, or lists, and visa-versa,
- Most everything in PSL is recursive,
- ODBC is supported for database work,
- Input and output files can be batched,
- PSL can be run from its own “hot folder”,
- Math can be done to any precision,
- Barcodes are generated – no fonts needed,
Jet letter has recently announced a Web Services product. Consequently, PSL can be run with full confidence on a web server such that, for example, a browser sends a request to run a PSL program against a set of data and return the resulting PDF file (perhaps only one) to the browser.
Web Services API's can also be used by on-line applications to invoke the PSL run-time environment on a local or remote server, perhaps where the printers are located.
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