Yeah, each line is one command. You can copy and paste it.
sed -i.bkp 's/^auth.\+pam_timestamp.so$/& timestamp_timeout=0/' config-util
This sed line makes a backup of file config-util, copying it to a file with prefix .bkp (config-util.bkp) and then updates the original file in place -- this is the -i
switch. The one-liner sed script uses a substitution command, s/what_to_look_for/replacement/, to update a line whose first characters are auth
and last ones pam_timestamp.so
. When it finds such a line it appends timestamp_timeout=0
to it, which is the option we want to modify from the default of 300.
You can do it by hand if you wish. It is a small modification.