[Info-vax] Command Procedure Pipe output to a variable

[VAXman- at SendSpamHere.ORG]

In article <36dd9084-f7f4-4316-a7e9-827fd0a7dc59n at googlegroups.com>, Jon Pinkley <jon.pinkley at gmail.com> writes:
>On Tuesday, August 31, 2021 at 6:05:33 PM UTC-4, VAXman- wrote:
>
>> Download and install SYMBOL. You can then read the help. In the interim, I'll 
>> look into why the 'helpgate' is failing.
>> -- 
>> VAXman- A Bored Certified VMS Kernel Mode Hacker VAXman(at)TMESIS(dot)ORG 
>> 
>> I speak to machines with the voice of humanity.
>
>As someone that has used TMESIS SYMBOL for more than 25 years, on VAX, Alpha 
>and Itanium, I will say it is well worth installing it.  It's incredibly flexible and useful 
>for many things.  You can see all scope levels of DCL symbols, the global plus 32 
>local scope levels (0-31), and with appropriate privilege, you can see the dcl symbols 
>(and procedures) being used by other processes, even processes on other cluster nodes.
>
>If makes debugging batch jobs much easier, because you are able to see the 
>"dcl variables" in use.

You ought to be using my DCL debugger to debug your batch job DCL.  With it, you 
can single step your DCL procedures and you have SYMBOL-like features and so much
more.



>And in addition to reading DCL symbols, you can also set them, a feature that can 
>be useful to affect a running batch job.
>
>Symbol can also be used to "return" a value to a local DCL symbol in the scope of 
>the invoker, using symbol /set/local/depth=-1
>
>example:  (this may be hard to follow, if you haven't played with DCL scoping)
>
>HP$ show symbol symbol
>  SYMBOL == "$SYS$SYSDEVICE:[SYMBOL]SYMBOL"
>HP$ symbol symbol
>[-]  SYMBOL == "$SYS$SYSDEVICE:[SYMBOL]SYMBOL"
>HP$ write sys$output f$environment("depth")
>0
>$ abc = "def"
>HP$ sho symbol /local abc
>  ABC = "def"
>HP$ @tt
>HP$ write sys$output f$environment("depth")
>1
>_HP$ symbol/show/local/depth=-1
>[0]  ABC = "def"
>_HP$ show symbol /local abc
>%DCL-W-UNDSYM, undefined symbol - check validity and spelling
>_HP$ show symbol abc
>  ABC = "def"
>_HP$ abc = "xyz"
>_HP$ sho sym abc
>  ABC = "xyz"
>_HP$ symbol/show abc
>[0]  ABC = "def"
>[1]  ABC = "xyz"
>_HP$ symbol/set/local/depth=-1 abc "ghi"
>_HP$ sho sym abc
>  ABC = "xyz"
>_HP$ symbol/show abc
>[0]  ABC = "ghi"
>[1]  ABC = "xyz"
>_HP$ symbol/show/local/depth=-1
>[0]  ABC = "ghi"
>_HP$ exit
>HP$ write sys$output f$environment("depth")
>0
>HP$ sho symbol abc
>  ABC = "ghi"
>HP$ sho symbol /local abc
>  ABC = "ghi"
>HP$
>
>In a command procedure it can even be used to see "who called me", a useful feature
>when you are trying to determine what is using a command procedure.
>
>$ symbol/show=(nosymbol,procedure) ! provide a call "traceback" 
>
>The point is, SYMBOL can do much more than the specific thing Brian explained.
>
>Highly recommended.

Thanks for your extolling words.
-- 
VAXman- A Bored Certified VMS Kernel Mode Hacker    VAXman(at)TMESIS(dot)ORG

I speak to machines with the voice of humanity.