The C library routines setjmp and longjmp provide functionality that cannot typically be used in the context of the ACUCOBOL-GT runtime. These routines provide "mark" and "goto" points in the call stack of C routines and sometimes provide a convenient exception-handling mechanism.
Because these routines do not know about the COBOL call stack, they cannot be used in cases where C routines call COBOL. However, the acusavenv() and aculongjmp() functions allow batch programs or programs written for a transaction processing system to restart or recover from a failed service component.
The acusavenv() and aculongjmp() functions are only usable from C and are not recommended for programs that use the ACUCOBOL-GT graphical user interface, which are typically event-driven and multithreaded.