🚀 go-pugleaf

( ... also posted to comp.lang.c)

In the ANSI standard under the description of the signal function,
(section 4.7.1.1) it states the following:

   "The function func may terminate by executing a return statement or
   by calling the abort, exit, or longjmp functions.  If func executes a
   return statement and the value of sig was SIGFPE or any other
   implementation-defined value corresponding to a computational
   exception, the behaviour is undefined.  Otherwise, the program will
   resume execution at the point it was interrupted.  If the signal
   occurs other than as the result of calling the abort or raise
   function, the behaviour is undefined if the signal handler calls any
   function in the standard library other than the signal function
   itself ..."

The last sentence implies that you can't call any library functions
(such as longjmp, abort or exit) from within the signal handler unless
the signal was explicitly raised through raise or abort.  But the first
three sentences imply that you can.  Can anyone explain this apparent
contradiction?

Jennifer Hamilton
IBM Toronto Lab
jennifer@torolab6.vnet.ibm.com