The sed keeps appending after repeating the play as I can't get the negative lookahead assertion to work, I think that's what it is?

Maybe that's what it is, and maybe it is because sed doesn't implement it. TIMTOWTDI also applies to sed: 

sed '/^GRUB_CMDLINE_LINUX=.*/ { /transparent_hugepage/! s/\(.*\)"/\1 t
+ransparent_hugepage=never"/}' $line

[download]

Using perl, things might be easier.

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re: GRUB Append Parameter in-between Quotes by shmem
in thread GRUB Append Parameter in-between Quotes by ephemeric

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