Syntax:
SHOW CREATE PROCEDURE proc_name

This statement is a MySQL extension. It returns the exact string that
can be used to re-create the named stored procedure. A similar
statement, SHOW CREATE FUNCTION, displays information about stored
functions (see [HELP SHOW CREATE FUNCTION]).

To use either statement, you must be the user named in the routine
DEFINER clause or have SELECT access to the mysql.proc table. If you do
not have privileges for the routine itself, the value displayed for the
Create Procedure or Create Function field will be NULL.

URL: http://dev.mysql.com/doc/refman/5.5/en/show-create-procedure.html

