<setjmp.h> <setjmp.h> typedef a-type jmp_buf; void longjmp(jmp_buf env, int val); #define setjmp(jmp_buf env) <int rvalue> Include the standard header <setjmp.h> to perform control transfers that bypass the normal function call and return protocol. jmp_buf typedef a-type jmp_buf; The type is the array type a-type of an object that you declare to hold the context information stored by setjmp and accessed by longjmp. longjmp void longjmp(jmp_buf env, int val); The function causes a second return from the execution of setjmp that stored the current context value in env. If val is nonzero, the return value is val; otherwise, it is 1. The function that was active when setjmp stored the current context value must not have returned control to its caller. An object with dynamic duration that does not have a volatile type and whose stored value has changed since the current context value was stored will have a stored value that is indeterminate. setjmp #define setjmp(jmp_buf env) <int rvalue> The macro stores the current context value in the array designated by env and returns zero. A later call to longjmp that accesses the same context value causes setjmp to again return, this time with a nonzero value. You can use the macro setjmp only in an expression that: has no operators has only the unary operator ! has one of the relational or equality operators (==, !=, <, <=, >, or >=) with the other operand an integer constant expression You can write such an expression only as the expression part of a do, expression, for, if, if-else, switch,, or while statement. See also the Table of Contents and the Index. Copyright © 1989-1996 by P.J. Plauger and Jim Brodie. All rights reserved.