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ZBasic System Library 143 ZX Microcontroller Family LongJmp Type Subroutine Invocation LongJmp(jmpbuf, val) Parameter Method Type Description jmpbuf ByRef Array of Byte A buffer holding the return context, see description below. val ByVal int16 The value to be returned to the original SetJmp() caller. Discussion This subroutine, in conjunction with SetJmp(), provides a way to circumvent the normal call-return structure and return directly to a distant caller. It is the equivalent of a non-local Goto function and can be used, among other purposes, to handle exceptions in your programs. The first parameter specifies a Byte array that has been previously initialized by a call to SetJmp(). The second parameter specifies a value that will be seen by the original SetJmp() caller as the return value. This value, which should be non-zero, can indicate the nature of the condition that led to the LongJmp() call. See the section on Exception Handling in the ZBasic Reference Manual for more details. Caution Passing a jump buffer that has not been prepared by a call to SetJmp(), one that has been modified after the SetJmp()call, or one that was prepared by a subroutine/function that is no longer active will have unpredictable and almost certainly undesirable effects. Compatibility This routine is not available in BasicX compatibility mode. See Also SetJmp