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Join line containing pattern to preceding line

Join line containing pattern to preceding line


I have a large file containing lots of data, however, I want to do the following;

Find any lines containing the pattern cn=

and join this line to the preceeding line (same as shift J in vi)- if that makes sense?

RE: Join line containing pattern to preceding line

Minor fix: add a space before the %s:


#--- Here ---V
#...{printf " %s"... 

The person who says it can't be done should not interrupt the person doing it. -- Chinese proverb

RE: Join line containing pattern to preceding line


Thanks for this, and it works great.

However, now I need to put this into a perl script & I am having issues with getting it to work. I have tried backticks, qq etc. and no good. Any ideas how to make this work within a perl script?

I run this ->

my $tmpfile_2 = qq|/tmp/somefile2.bak|;
my $awk_cn_command = qq|awk 'NR>1 && !/cn=/{printf '"\n"'}{printf '"%s"',$0}END{printf '"\n"'}' $logout > tmpfile_2|;
print $awk_cn_command;

and the output I get is;

awk 'NR>1 && !/cn=/{printf '"
"'}{printf '"%s"',./}END{printf '"
"'}' /tmp/failure.log > tmpfile_2awk: syntax error near line 2
awk: illegal statement near line 2

so the /n is breaking it for some reason...

RE: Join line containing pattern to preceding line

Figured out the issue; needed to be;

my $awk_cn_command = qq|awk 'NR>1 && !/cn=/{printf "\\n"}{printf "%s",\$0}END{printf "\\n"}' $tmpfile_1 > $tmpfile_2|;

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