LinuxQuestions.org - can't get the variable to set

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can't get the variable to set

doesn't seem to set or know about ADG_svrname env.

Works for me

Code:

$ cat test

#!/bin/ksh



Sdir=`dirname $0`



ADG_svrname=$Sdir/ADG_svrname.var

echo Writing $ADG_svrname

Code:

$ ./test

Writing ./ADG_svrname.var



$ ~/test

Writing /home/user/ADG_svrname.var

Where are you going with the rest of that if statement? There's no close in your example code.

Hi,

if I add a "fi" to the end of your script it works fine for me.

My ksh is:

Code:

% /bin/ksh --version

  version        sh (AT&T Research) 93u+ 2012-06-28

% dpkg -l ksh

Desired=Unknown/Install/Remove/Purge/Hold

| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend

|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)

||/ Name          Version      Architecture Description

+++-==============-============-============-==================================

ii  ksh            93u+20120628 amd64        Real, AT&T version of the Korn she

Is there any reason you want to use ksh? What about bash or just plain sh?

Evo2.

I am bit confusing of when you use ksh, sh or plain? which is which, could you please explain?

Hi,

it depends on your needs. For high portability and speed, straight bourne shell (sh) is probably best. For "features" bash is a good option.

IMHO, on a GNU/Linux system ksh is probably not such a good choice these days: bash has a similar feature set and is much more likely to be installed.

There is quite a bit on the web on this topic, and know that others here at LQ have opinions on this.

Cheers,

Evo2.

PS. I use zsh for my login shell, and a either bash or sh for scripting.

Using "sh" means you're executing the script in posix-compatibility mode. It may still be ksh, but restricted in features, or it may be a different shell entirely. You'll almost always want to use the full #!/bin/ksh shebang unless you really need portability.

Also, dirname, and the command substitution that goes with it, is unnecessary, since every major shell has at least basic parameter substitutions built in.

$(..) is highly recommended over `..` too.

QUOTE ALL OF YOUR VARIABLE SUBSTITUTIONS. You should never leave the quotes off a parameter expansion unless you explicitly want the resulting string to be word-split by the shell (globbing patterns are also expanded). This is a vitally important concept in scripting, so train yourself to do it correctly now. You can learn about the exceptions later.

http://mywiki.wooledge.org/Arguments
http://mywiki.wooledge.org/WordSplitting
http://mywiki.wooledge.org/Quotes

And learn how to format effectively too. At the very least indent your subsections.

Scripting With Style

Code:

#!/bin/ksh

if [[ $1 = "start" ]] ; then

        Sdir=${0##*/}

        ADG_svrname=$Sdir/ADG_svrname.var

        echo "Writing $ADG_svrname" >> tlog.txt

fi

#Final note, my links are all to bash sources, but almost all of it applies equally to ksh as well.

Quote:

within ADG_svrname.var, I am more interest of getting the value within this file and set it as a variable.

Show us the contents of the file then. Is it a single line, or multiple, or what?

Again, read is usually the command to use. Assuming there's only a single line:

Code:

read -r variable <filename

For multiple lines you'll probably have to use a while loop.

How can I read a file (data stream, variable) line-by-line (and/or field-by-field)?
http://mywiki.wooledge.org/BashFAQ/001

Then you just need to "source" that file, in order to execute every command/variable definition inside there:

Code:

. $Sdir/ADG_svrname.var

Code:

source $Sdir/ADG_svrname.var

This way, you'll have MYCURSOR=BLAH defined in your shell environment and you'll be able to use that thereon.

Excuse me, why did you delete your opening post? (And most of the following ones too?) You've now made it harder for readers to follow the rest of the thread. That's considered rather impolite, to say the least. Please don't do it again.

There's nothing to be embarrassed about, if that's your reason. Everybody is new sometime, and we all make mistakes. All criticisms given were only to help you with your problem and to improve your skill.

Moderator note: @brian00: I don't see any reason for deleting your question and subsequent feedback, especially after having received useful answers from other LQ members. This is not respectful towards people that voluntarily spent some of their time to help you! Please, refrain from doing that in the future. Thread closed.

I am sorry, won't do it again