Bunset
From Scriptwiki
The bunset command is used to unset a binary file.
bunset <&binvar> [&binvar &binvar ... &binvar]
This unsets all specified binary files. Unlike unset, bunset doesn't work with wildcards.
Examples
bset &test 1 65 66 67 echo -a $bvar(&test,0) returns 3 bunset &test echo -a $bvar(&test,0) returns 0
In this case the first echo will echo 3 as &test is filled with 3 bytes, the second echo will echo 0 as &test is unset.
bset &test 1 65 66 67 bset &another 1 97 98 echo -a $bvar(&test,0) returns 3 echo -a $bvar(&another,0) returns 2 bunset &test &another echo -a $bvar(&test,0) returns 0 echo -a $bvar(&another,0) returns 0
This is an example of two binary files being unset with one command.