As you mentioned, TIMTOWTDI. I think I'd rather stick with doing more with bash since that's what most of the script is in. If you want a one-liner you could always separate the parts with a ; :-). Something like:

if grep -v -q 'the_line' ld.so.conf; then echo 'the_line' >> ld.so.con
+f; fi

[download]
You probably already thought of this, but I figured I'd document it for posterity's sake.

Do not rebuke them with harsh words ... but rather lead them gently - with URLs - so that they may learn wisdom.

In reply to Re: quick way to add a line to a file, if it's not already present (automating tweaking of /etc/ld.so.conf for installing Image::Magick) by VSarkiss
in thread quick way to add a line to a file, if it's not already present (automating tweaking of /etc/ld.so.conf for installing Image::Magick) by tphyahoo

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