linux - What does `!:-` do? -


i new bash scripting , in ubuntu\debian package system.

today studying content of preinst file script executes before package unpacked debian archive (.deb) file.

my fist doubt line containing this:

!:-

probably stupid question but, using google, can't find answer.

insert last command without last argument (bash)

/usr/sbin/ab2 -f tls1 -s -n 1000 -c 100 -t 2 http://www.google.com/

then

!:- http://www.stackoverflow.com/

is same as

/usr/sbin/ab2 -f tls1 -s -n 1000 -c 100 -t 2 http://www.stackoverflow.com/

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