longjmp : longjmp « setjmp.h « C Tutorial

1. C Tutorial
2. setjmp.h
3. longjmp

1. The longjmp() function causes program execution to resume at the point of the last call to setjmp().
2. longjmp() and setjmp() provide a means of jumping between functions.

The most common use of longjmp() is to return from a deeply nested set of routines when an error occurs. (C: The Complete Reference, Fourth Edition by Herbert Schildt McGraw-Hill/Osborne 2000 ISBN-10: 0072121246, ISBN-13: 978-0072121247)

#include <setjmp.h>
  #include <stdio.h>

  jmp_buf ebuf;
  void f2(void);

  int main(void)
  {
    int i;

    printf("1 ");
    i = setjmp(ebuf);
    if(i == 0) {
      f2();
      printf("This will not be printed.");
    }
    printf("%d", i);

    return 0;
  }

  void f2(void)
  {
    printf("2 ");
    longjmp(ebuf, 3);
  }

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