> irb(main):024:0> a = 'test' << 0
> "test\000"
> irb(main):025:0> a.delete!(  )
> 
> What do I pass to delete! in order to remove the null 
> character? (Can't use
> chop, it may not always be there in the data I'm working with)

Well, this works, but is there a more concise way to do it:

irb(main):030:0> a = 'test' << 0
"test\000"
irb(main):031:0> b = ''
""
irb(main):032:0> a.each_byte do |byte| b << byte if byte != 0 end
"test\000"
irb(main):033:0> b
"test"