remove leading space and join previous line

[Iko]

hello community!

i have a text file (it`s a ldif export), and i would like to grep out the dn. the line with the dn starts with "dn:". no problem so far to grep for this pattern.
but the ldif export makes a line break after 76 characters, and continues the next line with a "space" character.

since i need the full dn, i need a way to:
1) search for this lines which start with a leading "space"
2) remove this "space"
3) and finally join the line which had the space, with the previous line

i have tried several ways with sed, awk, tr, ... but since i´m quite new to this topics i dont get it solved. does anyone here have a hint for me, how to do this task?

thanks in advance,
iko

[vamped1]

Perl seems like an obvious tool for this. Here is a rough hack that may get you started. Put this on the command line:

perl -ne 'use feature "state"; state $join_it=0; if ($join_it==1) { if (s/^ //) { print } else { print "\n" }; $join_it=0 }; if (/^dn:/) { chomp; print; $join_it=1 }' dn_file

p.s. I'm not a programmer, so forgive any bad style.

[Iko]

ty vamped1.

in the meantime i got a solution which is more compact and is exactly what i need.
for everyones interest:
sed -e :a -e '$!N;s/\n //;ta' -e 'P;D' filename

br, iko