Very Computer

Hello. I've a couple of (probably elementary) questions about shell
programming. Any help on these, including good references for the novice
shell programmer, would be greatly appreciated.

1) Is it possible to/how does one change the value of a shell or
environment variable from within a subshell?  The application I have
in mind is modifying the display variable with a shell script.

2) Alternatively, I've tried:
     alias disp setenv DISPLAY '"grad"$1":0"'
where the intended result of:  disp 01  would be
     setenv DISPLAY grad01:0
Instead the command is formatted like:
     setenv DISPLAY grad:0 01
Any suggestions on how this approach could be made to work?

Thanks in advance for any help. Replies by e-mail or follow-up posts
are fine.

Mike Buksas
--
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919/571-1339            |  919/515-7321                    | Or probably yours.
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Quote:

>1) Is it possible to/how does one change the value of a shell or
>environment variable from within a subshell?  The application I have
>in mind is modifying the display variable with a shell script.

Quote:>2) Alternatively, I've tried:
>     alias disp setenv DISPLAY '"grad"$1":0"'
>where the intended result of:  disp 01  would be
>     setenv DISPLAY grad01:0
>Instead the command is formatted like:
>     setenv DISPLAY grad:0 01

Quote:>Any suggestions on how this approach could be made to work?

>Mike Buksas

Quote:>Hello. I've a couple of (probably elementary) questions about shell
>programming. Any help on these, including good references for the novice
>shell programmer, would be greatly appreciated.
>1) Is it possible to/how does one change the value of a shell or
>environment variable from within a subshell?  The application I have
>in mind is modifying the display variable with a shell script.
>2) Alternatively, I've tried:
>     alias disp setenv DISPLAY '"grad"$1":0"'
>where the intended result of:  disp 01  would be
>     setenv DISPLAY grad01:0
>Instead the command is formatted like:
>     setenv DISPLAY grad:0 01
>Any suggestions on how this approach could be made to work?

Quote:> Hello. I've a couple of (probably elementary) questions about shell
> programming. Any help on these, including good references for the novice
> shell programmer, would be greatly appreciated.
> 1) Is it possible to/how does one change the value of a shell or
> environment variable from within a subshell?  The application I have
> in mind is modifying the display variable with a shell script.

Csh uses:
source your_script

And your current shell will get any variable changes.
--
        -joe        "Honey, they're in *everybody's* eggs" --firesigns

Quote:>  setenv does not accept any arguments.  It does, although, accept
>environment variables.  If $1 were a valid environment variable name
>_before_ this alias command was executed then you would get the
>correct outcome.

This is slightly misleading... setenv "accepts" environment variables
only in the sense that your shell performs variable substitution on
a command line before executing the command(s) that it contains.

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