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Michael Homer

01:00

If it's not too broad then it's an obvious duplicate, but the question is "How to install tar file globally".

I think your answer illustrates how broad it is even on that narrower interpretation.

GoboLinux does install with /usr as prefix and just sandboxes the files out these days, too, though it doesn't really undercut your point.

8 hours later…

alamin

09:10

Hi, Is anyone here?

Kusalananda

(no?)

;-)

@alamin Yes, I'm most definitely here. The only problem is that my cup of coffee isn't.

alamin

can i ask a simple question

Kusalananda

(coffee cup found, all is well)

@alamin Do it

alamin

what is the function of set?

set command

set arg1 arg2 arg3

why we need to use this command for?

Kusalananda

@alamin That will set the positional parameters $1, $2 and $3 to the specified values.

Then you could do for thing; do ... done to iterate over them.

alamin

09:18

when we run a script don't we give the args there and the positional parameters are made automatically from those args... so how this command can help me. is there any more usage?

Kusalananda

It's not used that way often. I would have to dig out a real world example... hold on.

alamin

all right .... i will wait for the response

set foo bar dream sky blue

for var in $@

echo $var

done

OUTPUT:

foo
bar
dream
sky
blue

Kusalananda

You don't even need the in $@.

alamin

why?

don't I need the collection?

Kusalananda

Because for will use the positional parameters if not given anything else.

alamin

09:25

so how do I write this?

for var
do

Kusalananda

yep

alamin

well, let me try

yes it works...

another question came to my mind?

setting to a null string, isn't equivalent to unsetting it

what does that mean?

Kusalananda

Not really the same thing. There was a question about this a while ago.

alamin

Another Thing Are you Indian? Cause Your Name Suggest it ...

Kusalananda

A: Are the null string and "" the same string?

Yes, a null string in that context is a string of length 0 containing no byte at all. In bash: var= var='' var="" var=$'' var=$"" var=$(true) # or any command that outputs nothing or only newline # characters var=`true` var=${null_or_unset_var} var=''""$''$""$(true)"`true`" But als...

@alamin :-) No, not Indian. Long story...

Also: unix.stackexchange.com/a/121558/116858

alamin

09:30

I would like to hear it some day :D

Kusalananda

set is more often used for setting shell options, as with set -x.

alamin

all right... tell me more ... like setting environment variables or something?

Kusalananda

@alamin No, in bash, type help set to get its documentation.

2 hours later…

alamin

11:36

anyone?

Kusalananda

Just me, sorry :-)

Faheem Mitha

11:57

@Kusalananda Apparently today is shell tutoring day.

1 hour later…

Kusalananda

13:01

@FaheemMitha Every day is shell tutoring day in one corner or the other :-)

1 hour later…

Kusalananda

14:11

Closing that wa a bit harsh... unix.stackexchange.com/questions/390091/…

Esp. since I just solved it ;-)

1 hour later…

Faheem Mitha

15:22

@Kusalananda Do you want me to cast a reopen vote? I see there is one - is that you?

Kusalananda

@FaheemMitha Yes, that's me. I dunno. The question is clear to me...

Faheem Mitha

@Kusalananda So that's a yes on casting a reopen vote?

You should know that one of my idiosyncrasies is that I like direct answers to questions.

If I lived in a romantic comedy it would probably be a charming foible.

Kusalananda

15:50

@FaheemMitha :-) It's a "Yes, if you think the question is worth reopening".

I hate telling people what to do.

Faheem Mitha

@Kusalananda I'll take your word for it. It's not life or death.

@Kusalananda That's very noble of you.

I see it's got -3, so some people are not impressed.

Actually, it's indeed unclear what the question is asking. Did you figure it out?

Kusalananda

Well, a good answer can still be written. Yes, he wants to get all lines between the first and lost occurance of a certain word.

This is actually non-trivial and quite an interesting problem.

Faheem Mitha

Oh, I see. He wants section bookended by the End delimiter to be preserved.

Kusalananda

You see my solution in comments, but I could write more about it.

Faheem Mitha

Is that correct?

Kusalananda

15:53

Yes, I believe so.

Faheem Mitha

Though if so, he's expressing it very poorly.

I'd suggest rewording it. I'll vote to reopen, but it would encourage more people to do so.

Kusalananda

The naive solution with sed doesn't work: /End/,/End/p

Faheem Mitha

@Kusalananda Does your comment not work, then?

Kusalananda

My comment works

Faheem Mitha

@Kusalananda Ok.

Kusalananda

15:54

... by working on the beginning of the file, reversing it and doing the same thing again before reversing it a second time.

Faheem Mitha

I'd improve the question's wording.

Kusalananda

Do so. I need to feed my girl.

BTW, am I correct here?: stackoverflow.com/a/46025153/4941495

Regarding let and expr

Faheem Mitha

@Kusalananda Fine. How's that?

@Kusalananda You'll have to wait for someone who knows shell.

This one seems like a VTC candidate.

Q: Accidentally removed /usr/local/bin/node

I accidentally copied the following command from a forum into my command line sudo ln -fs /usr/bin/nodejs /usr/local/bin/node which caused /usr/local/bin/node to get deleted (replaced by a dead link). I didn't need to run that command since I don't have /usr/bin/nodejs, I just pasted the wrong...