numbers from egrep result in one line - grep

Question

I use egrep to output some lines with platform names:
XXX | egrep "i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$"
[30] i686-nptl-linux-gnu
[34] i686-w64-mingw32
[75] x86_64-unknown-linux-gnu
[77] x86_64-w64-mingw32
what I need is:
export PLATNUMS=30,34,75,77
How can I pipe the egrep command to sed / awk / bash script?

Answer 1

Try:
$ command | awk -F'[][ \t]+' '/i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$/{printf "%s%s",(f?",":"export PLATNUMS="),$2; f=1} END{print""}'
export PLATNUMS=30,34,75,77
How it works
-F'[][ \t]+'
Use any number of spaces, tabs, or [ or ] as field separators.
/i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$/{...}`
For the lines of interest, perform the commands in curly braces.
printf "%s%s",(f?",":"export PLATNUMS="),$2; f=1
For the lines of interest, print what we want.
The variable f marks whether this is the first line of interest.
END{print""}
After reading all lines, print a newline.
Creating a shell variable
export PLATNUMS=$(command | awk -F'[][ \t]+' '/i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$/{printf "%s%s",(f?",":""),$2; f=1} END{print""}')
For example, if the file input contains your data:
$ export PLATNUMS=$(awk -F'[][ \t]+' '/i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$/{printf "%s%s",(f?",":""),$2; f=1} END{print""}' input)
$ declare -p PLATNUMS
declare -x PLATNUMS="30,34,75,77"
For those who prefer their commands spread out over multiple lines:
export PLATNUMS=$(command | awk -F'[][ \t]+' '
/i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$/{
printf "%s%s",(f?",":""),$2
f=1
}
END{
print""
}
')

Answer 2

Perhaps this way, I can't try with your egrep.
export PLATNUMS=$(XXX | egrep "i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$" | sed ':A;s/\[\([[0-9]*\)].*/\1/;$bB;N;bA;:B;s/\n/,/g')
echo $PLATNUMS
How this work ?
Your egrep command return a multiline text
so sed read this text line by line this way
sed '
:A # label A
# here with your example
# on the first line the pattern space look like that
# [30] i686-nptl-linux-gnu
# on the second line the pattern space look like
# 30
# [34] i686-w64-mingw32
s/\[\([[0-9]*\)].*/\1/ # substitute all digit enclose by [] by only the digit
# on the first line the pattern space become
# 30
# on the second line the pattern space become
# 30
# 34
# and so on for each line
$bB # on the last line jump to B
N # get a newline in the pattern space
bA # It is not the last line so jump to A
:B # label B
# here we have read all the line
# the pattern space look like that without the #
# 30
# 34
# 75
# 77
s/\n/,/g' # subtitute all \n by a comma
# the pattern space become
# 30,34,75,77
# $(XXX | egrep .... | sed ...) return 30,34,75,77 in the variable PLATNUMS
# It is better not to use all capital letters in your variable name

Answer 3

With GNU sed and tr:
$ XXX | egrep "i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$" | sed -E 's,]\s+.+$,,g' | sed 's,^\[,,g' | tr '\n' ',' | sed -E 's,(^.+$),export PLATNUMS=\1,' | sed 's/,$//' && echo
I'm not sure what you want to achieve but you might want to automatically eval the output export:
$ eval $(XXX | egrep "i686-nptl-linux-gnu$|i686-w64-mingw32$|x86_64-unknown-linux-gnu$|x86_64-w64-mingw32$" | sed -E 's,]\s+.+$,,g' | sed 's,^\[,,g' | tr '\n' ',' | sed -E 's,(^.+$),export PLATNUMS=\1,' | sed 's/,$//' && echo)
$ echo $PLATNUMS
30,34,75,77

Answer 4

If you ever think you need grep+sed or 2 greps or 2 seds or any other combination then you should use 1 call to awk instead, and you never need grep or sed when you're using awk:
export PLATNUMS=$(XXX | awk -F'[][]' '/(i686-nptl-linux-gnu|i686-w64-mingw32|x86_64-unknown-linux-gnu|x86_64-w64-mingw32)$/{p=(p ? p "," : "") $2} END{print p}')
Btw in case it's useful, here's a couple of briefer regexps:
(i686-(nptl-linux-gnu|w64-mingw32)|x86_64-(unknown-linux-gnu|w64-mingw32))$
((i686-nptl|x86_64-unknown)-linux-gnu|(i686|x86_64)-w64-mingw32)$
and depending on your input data (since this will include combinations not provided by the above) you MIGHT only need:
(i686|x86_64)-(nptl|unknown|w64)-(linux-gnu|mingw32)$