johnf@runx.ips.oz (John F. Baird) (07/28/87)
Here's why it's not an excellent idea to abbreviate DCL symbols like this; $ PH*ONE == "PHONE/ANSWER" Because DCL will create a symbol entry for each combination, PH, PHO, PHON, and PHONE, in its internal tables. I found this when I was wandering through P1 space for a process using the ANALYSE/SYSTEM command. I'm sure it's alright to use abbreviations, but when you are worried about performance and resources, it may not be a good idea. We removed all abbreviated symbols from our captive application usernames, since they were static. James Cameron via ACSnet johnf@runx.ips.oz
heisterb@uiucuxe.cso.uiuc.edu (08/03/87)
Another good example of the problem with abbreviated symbols is $ del*ete == "DELETE/LOG" Then try to delete the symbol delete! This is a real-life example, too, I saw it happen, really! DJ Heisterberg National Center for Superconfusing Applications heisterb@uxe.cso.uiuc.edu 13004@ncsa[a|b].ncsa.uiuc.edu
u3369429@murdu.OZ (Michael Bednarek) (08/05/87)
In article <62500005@uiucuxe> heisterb@uiucuxe.cso.uiuc.edu writes: >Another good example of the problem with abbreviated symbols is > $ del*ete == "DELETE/LOG" >Then try to delete the symbol delete! This is a real-life example, too, I saw >it happen, really! This is a good opportunity to point to the 'undocumented feature' of DCL which accepts commands with trailing superfluous characters: $ Deleteit/Symbol/Global delete works perfectly in the situation described above. There is a funny story to this around here: The system-wide login procedure used to create LO*GOUT==@SYS_SYSTEM:LOGOUT which attempted to get the user to purge files. The first prompt was usually answered by hitting 'Y'. All users in our department logged out with: $ LOGOUTY and were not prompted. It took me about three months when I started here to understand what was going on. I, of course, always logged out with $ EOJ . Anyway, back to the scenario above. Of course, the command: $ del/Symbol/Global delete works as well, only you get a message: %DCL-I-IGNQUAL, ..., but it still works. Michael Bednarek u3369429@{murdu.oz.au | ucsvc.dn.mu.oz.au} Institute of Applied Economic ...{UUNET.UU.NET | seismo.CSS.GOV}!munnari! and Social Research (IAESR) {murdu.oz | ucsvc.dn.mu.oz}!u3369429 Melbourne University mb@munnari.oz.au Parkville 3052, Phone : +61 3 344 5744 AUSTRALIA "POST NO BILLS."
heisterb@uiucuxe.cso.uiuc.edu (08/05/87)
Thanks for all the suggestions about del*ete = delete/log, except I wasn't asking for help, I'm not that lame. This definition affected a user who had learned just enough about DCL to get himself in trouble. I thought it was a humourous example. Next time I post (if ever) I'll clearly state whether I'm an idiot or not. There's nothing like getting a dozen mail messages in the morning, half of which tell you how stupid you are because the problem's so easy. No more mail, please! DJ Heisterberg (I thought including name and address was friendly, I guess I know better now)
ive%tonys.span@VLSI.JPL.NASA.GOV (08/05/87)
What exactly is wrong with deleting symbol del besides a warning message saying that the /LOG parameter was ignored. Moreover, I use $ DEL*ET == "DELETE/LOG". When I need to delete DEL, I say $ DELETE/SYM/GLO DEL. That works warning message free. -------
F1142S30%unika2@germany.CSNET (Juergen Renz) (08/06/87)
In message <62500005@uiucuxe> DJ Heisterberg writes: >Another good example of the problem with abbreviated symbols is > > $ del*ete == "DELETE/LOG" > >Then try to delete the symbol delete! This is a real-life example, too, I saw >it happen, really! My solutions are: $ delete :== or $ delete == "" or $ deleee /symbol /global delete ! Note: only the first 4 characters ! are significant I have another problem with abbreviated symbols: First define an abbreviation for TPU: $ ed*it :== edit/tpu Then define a symbol for EDT: $ edi :== edit/edt The second command fails. So I have to define three symbols: $ ed :== edit/tpu $ edi :== edit/edt $ edit :== edit/tpu Has anyone got a solution for that? P.S.: The definitions for EDT and TPU are only examples. I use to define my abbreviations carefully. Juergen Renz Universitaet Karlsruhe Falkengarten 7 Institut fuer Informatik IV D-7530 Pforzheim West-Germany