method
delete_all
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delete_all(# :yield: message)
public
Deletes all messages on the server.
If called with a block, yields each message in turn before deleting it.
Example
n = 1 pop.delete_all do |m| File.open("inbox/#{n}") do |f| f.write m.pop end n += 1 end
This method raises a POPError if an error occurs.