Suggestions for "User" command.

[Dave Snyder]

----- Original Message -----
| From: "Brian K. White" <brian at aljex.com>
| To: filepro-list at lists.celestial.com
| Sent: Wednesday, March 2, 2011 6:16:28 PM
| Subject: Re: Fwd: Suggestions for "User" command.
| On 3/2/2011 5:09 PM, Dave Snyder wrote:
| > ----- Forwarded Message -----
| > | From: "Dave Snyder"<dave at wisvis.com>
| > | To: "Kenneth Brody"<kenbrody at spamcop.net>
| > | Sent: Wednesday, March 2, 2011 4:01:00 PM
| > | Subject: Re: Suggestions for "User" command.
| > | ----- Original Message -----
| > | | From: "Kenneth Brody"<kenbrody at spamcop.net>
| > | | To: "Dave Snyder"<dave at wisvis.com>
| > | | Cc: filepro-list at lists.celestial.com
| > | | Sent: Wednesday, March 2, 2011 3:44:46 PM
| > | | Subject: Re: Suggestions for "User" command.
| > | | On 3/2/2011 4:33 PM, Dave Snyder wrote:
| > | | [... Exiting a USER command ...]
| > | |>
| > | |>  Anyone have any brilliant ideas for ending the external
| > | |>  program
| > | |>  besides my @keyX solution.
| > | | [...]
| > | |
| > | | Yes. When your program receives EOF on stdin, exit. No need for
| > | | any
| > | | special "I need to tell the USER program that I'm exiting"
| > | | logic.
| > | |
| > | | --
| > | | Kenneth Brody
| >
| >
| > I understand. But when I get to the next record (remember that I'm
| > in
| > *clerk) and try to use the external program, I have a problem. I
| > originally
| > thought that the
| >
| > if not program
| > then user program = /appl/bin/ext-prog
| >
| > logic would just start the external script again, but that doesn't
| > seem to be the case.
| 
| I use user in a only a few, but very frequently and heavily used
| routines and I don't have special exit logic in the user command other
| than what Ken said, nor do I ever close aliasname, nor do I have a
| problem with child processes being left behind.
| 


I think Mark solved my problem by suggesting that I CLOSE the alias.  Never
thought about using CLOSE in that context. Use it to close a LOOKUP alias of 
course but didn't think of it with a USER alias. After the close, if I need
the USER routine again, the IF NOT ALIAS construct seems to work. At least that's 
what I'm seeing so far. It seems to be more about telling *clerk that the
alias is no longer valid and less about actually "closing" anything.


Brian: I understand what you are saying. I also have my script run in a WHILE loop.
First thing that the script expects is a directive for a case statement.
For example alias=TIMESTAMP. The next thing that I send it is a format for the
date command. I get back a date in the requested format (down to nano seconds with TZ).
It then returns to the while loop.

Or my directive might be PASSWORD, which runs a section that expects the next
argument to be an account number.  It then retrieves a password from MYSQL and returns
that to filepro.

Or I tell it COMMAND.  It then expects a fully built SQL command. If I send it an UPDATE,
move on. If I send it a SELECT or INSERT, better catch the return. :)  

Makes it very easy to have 1 USER routine that can be used for very specific things
like the TIMESTAMP of PASSWORD examples. But can also be used for any *nix command where
SYSTEM isn't appropriate because a reply is expected.

Thanks All!


Regards,

Dave Snyder
dave at snyderz.org