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Full Discussion: SIGSEGV Signal handling
Special Forums UNIX and Linux Applications SIGSEGV Signal handling Post 302342011 by jim mcnamara on Friday 7th of August 2009 07:22:37 AM
Old 08-07-2009
First off, do not run code in production that gets a SIGSEGV signal. It is really bad practice.

The simplest way, and definitely not the best is to block the signal with a call to signal()
Code:
#include <signal.h>
#include <stdio.h>

void my_signal_handler(int sig)
{
    write(STDERR_FILENO, "SEGFAULT!\n", 10); 
    signal(SIGSEGV, my_signal_handler); // reset the signal handler for SIGSEGV
    abort();
}

int main()
{
   signal(SIGSEGV, my_signal_handler); // initial set of signal handler
   /* do stuff here  */
   signal(SIGSEGV, SIG_DFL);  // restore default behavior

}

This is an example not meant to be used for production - it has potential race conditions, but you can use it to debug a SIGSEGV problem. In the my_signal_handler function be aware that you need to call only async safe functions like write() not std C lib funcions like printf()
 

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LEARN ABOUT SUNOS

_stack_grow

_stack_grow(3C) 					   Standard C Library Functions 					   _stack_grow(3C)

NAME

       _stack_grow - express an intention to extend the stack

SYNOPSIS

       #include <ucontext.h>

       void *_stack_grow(void *addr);

DESCRIPTION

       The  _stack_grow()  function indicates to the system that the stack is  about to be extended to the address specified by addr. If extending
       the stack to this address would violate the stack boundaries as retreived by stack_getbounds(3C), a SIGSEGV is raised.

       If the disposition of SIGSEGV is SIG_DFL, the process is terminated and a core dump is generated.  If the application has installed its own
       SIGSEGV handler to run on the alternate signal stack, the signal information passed to the handler will be such that a call to stack_viola-
       tion(3C) with these parameters returns 1.

       The addr argument is a biased stack pointer value. See the Solaris 64-bit Developer's Guide.

       This function has no effect if the specified address, addr, is within the bounds of the current stack.

RETURN VALUES

       If the _stack_grow() function  succeeds and does not detect a stack violation, it returns addr.

ERRORS

       No errors are defined.

USAGE

       The _stack_grow() function does not actually adjust the stack pointer register. The  caller  is	responsible  for  manipulating	the  stack
       pointer register once _stack_grow() returns.

       The  _stack_grow()  function  is typically invoked by code created by the compilation environment prior to executing code that modifies the
       stack pointer. It can also be used by hand-written assembly routines to allocate stack-based storage safely.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Async-Signal-Safe 	   |
       +-----------------------------+-----------------------------+

SEE ALSO

       stack_getbounds(3C), stack_inbounds(3C), stack_violation(3C), attributes(5)

       Solaris 64-bit Developer's Guide

SunOS 5.10							    18 Jul 2002 						   _stack_grow(3C)
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