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Unwanted execution instead of saving to environment variable

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# 1  
Old 10-30-2014
Unwanted execution instead of saving to environment variable
My .bash_profile file: source
Code:
$HOME/build.variables

My build.variables file:
Code:
export threads="$(${threads:-$(lscpu | egrep "CPU\(s\):|Thread" | $[$(sed -e:a -e "/$/N; s@CPU.*\([[:digit:]]\)\n.
*Thread.*\([[:digit:]]\)@\1*\2@;Ta")])})"

Code:
threads=$(lscpu | egrep "CPU\(s\):|Thread" | $[$(sed -e:a -e "/$/N; s@CPU.*\([[:digit:]]\)\n.*Thread.*\([[:digit:]]\)@\1*\2@;Ta")

The above codes when not comment out results in bash message, "-bash: 8: command not found" (because I have a 4 core cpu * 2 threads each). I tried other combination of brackets, backticks,echos, 2>&1 etc. with no success so far. I want to export the number, "8" not execute it. Thanks for your time.
# 2  
Old 10-30-2014
How about this:

Code:
export threads=$(lscpu | awk '/^CPU\(s\):/ {CPU+=$NF} /Thread/ {TH=$NF} END{ print CPU*TH}')

# 3  
Old 10-30-2014
Thanks for the effort. I should have mentioned I was not looking for another method for achieving the result but I am thinking maybe there was a bracket modification, quotes addition or pipe addition to solve the problem or an understanding of what is causing the fail and why a slight modification will never work.

I suspect that bash math brackets, "$[]" want to act as an executable not matter what in brackets, "$()" and I was wondering if it is possible to change that behaviour.
# 4  
Old 10-30-2014
Way to many levels of $() and $[]

This should "work"
Code:
export threads="${threads:-$(($(lscpu | egrep "^CPU\(s\):|Thread" |
    sed -e:a -e "/$/N; s@CPU.*\([[:digit:]]\)\n.*Thread.*\([[:digit:]]\)@\1*\2@;Ta")))}"

Edit: Note I added "^" (Beginning of line match) to the CPU grep RE, as on my system, lscpu was also outputting the following line, which the grep was (incorrectly) catching:

Code:
NUMA node0 CPU(s):     0,1

Last edited by Chubler_XL; 10-30-2014 at 11:10 PM..
This User Gave Thanks to Chubler_XL For This Post:
charlieandlinux
# 5  
Old 11-01-2014
Impressive. I still have to study what different brackets do. The following might be the final revision, which you helped create, to be used in a new method of building xorg git:

Code:
export threads=$(($(lscpu | egrep "^CPU\(s\):|Thread" | sed -e:a -e "/$/N; s@C.*\([0-9*]\)\nT.*\([0-9*]\)@\1*\2@;Ta")))

Also, could I infer that by the word, "incorrectly" that I should report to the grep maintainer the unexpected behavior of catching the following line?
# 6  
Old 11-01-2014
Quote:
Originally Posted by charlieandlinux
[...]Also, could I infer that by the word, "incorrectly" that I should report to the grep maintainer the unexpected behavior of catching the following line?
What you should infer is that an unforeseen result was produced because the original regular expression `"CPU\(s\):|Thread"' was able to match the following line, outputted by lscpu:
Code:
NUMA node0 CPU(s):     0,1

This is correct since it satisfies the regex by matching the part CPU(s):
In order to exclude that unwanted match, the beginning of line anchor was added later on.
Code:
"^CPU\(s\):|Thread"

Letting only match like these be the acceptable result:
Code:
CPU(s):                x
Thread(s) per core:    x

Even when, maybe, just in case, it should be
Code:
"^CPU\(s\):|^Thread"

if the lesson was learned.
Last edited by Aia; 11-01-2014 at 02:50 AM.. Reason: Adding matching part
This User Gave Thanks to Aia For This Post:
Chubler_XL
# 7  
Old 11-01-2014
No lesson on my part can be learned. Only a misunderstanding of language corrected. I incorrectly understood that, "lscpu was also outputting the following line, which the grep was (incorrectly) catching" meant that grep was returning the next line after "CPU(s):" (two different lines total) which would be "On-line CPU(s) list" on my system but some unknown line after "Numa node CPU(s):" on his computer which I don't have on my computer. Therefore I thought egrep had a bug of returning two lines on his machine and only one on mine.

But the difference between your clarification and chubler is that yours adds that the unforeseen result was due to the regular expression and omits the former statement of 'grep being incorrect'.
Last edited by charlieandlinux; 11-01-2014 at 03:22 AM..
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