void longjmp (jmp_buf env, int val);

<setjmp>

Long jump

Restores the environment by the most recent invocation of the setjmp macro in the same invocation of the program. The information required to restore this environment is provided by parameter env, whose value is obtained from a previous call to setjmp.

The function never returns to the point where it has been invoked. Instead, the function transfers the control to the point where setjmp was used to fill the env parameter.

Parameters

env

Object of type jmp_buf containing information to restore the environment at the setjmp's calling point.

val

Value to which the setjmp expression evaluates.

Return value

Example

/* longjmp example */
#include <stdio.h>
#include <stdlib.h>
#include <setjmp.h>

main()
{
  jmp_buf env;
  int val;

  val=setjmp(env);

  printf ("val is %d\n",val);

  if (!val) longjmp(env, 1);

  return 0;
}

Output:

val is 0
val is 1

See also