READ_TAIL

READ_TAIL(C command_tail)

U command_tail

READ_TAIL reads a command tail where a program is specified on the command line. This function does not work for command tails passed using %CALL. Once a command tail has been read using either READ_TAIL or READ_TOGGLE, it cannot be re read
There are two ways of using this function. If you specify a command tail name, READ_TAIL reads the parameter after the specified command tail. (Use READ_TOGGLE to check for a command tail that has no parameter.) If you do not specify a command tail, On Win32 and Unix platforms READ_TAIL will read the next command tail that does not begin with a −. On legacy platforms READ_TAIL will read the next command tail regardless of whther or not it begins with a −.

It is best to use READ_TAIL with a command tail name unless you want to specify a list of similar items. You should call READ_TAIL() and READ_TOGGLE() to check for all the possible named command tails before reading command tails without a name.

given command tails of GEORGE FRED −HENRY B
READ_TAIL("HENRY") = "B"
READ_TAIL("") = "GEORGE"
READ_TAIL("") = "FRED"