signals (SIGBUS and SIGSEGV)

[junky_fellow]

what is the difference between signals SIGBUS and SIGSEGV ?
when does an application program receive SIGBUS and in which
cases SIGSEGV ?

thanx in advance for any help ...

[Ulrich Eckhardt]

junky_fellow wrote:

what is the difference between signals SIGBUS and SIGSEGV ?
when does an application program receive SIGBUS and in which
cases SIGSEGV ?

Neither of them are defined by the C language, so in order to get info you
better also say which operating system and then take all that to an OS
specific group.
That said, google didn't take me more than a minute to find something(ok, I
knew what I was looking for, but ...).

Uli

[Ben Pfaff]

Ulrich Eckhardt <do******@knuut.de> writes:

junky_fellow wrote:

what is the difference between signals SIGBUS and SIGSEGV ?
when does an application program receive SIGBUS and in which
cases SIGSEGV ?

Neither of them are defined by the C language, so in order to get info you
better also say which operating system and then take all that to an OS
specific group.

On the contrary, SIGSEGV is defined by the C standard as "an
invalid access to storage". SIGBUS is, as you say, not defined
as part of C.
--
"C has its problems, but a language designed from scratch would have some too,
and we know C's problems."
--Bjarne Stroustrup

[Kenneth Brody]

junky_fellow wrote:

what is the difference between signals SIGBUS and SIGSEGV ?
when does an application program receive SIGBUS and in which
cases SIGSEGV ?

thanx in advance for any help ...

OT for comp.lang.c, but...

http://www.brainboost.com/search.asp...and+SIGSEGV%3F

--
+-------------------------+--------------------+-----------------------------+
| Kenneth J. Brody | www.hvcomputer.com | |
| kenbrody at spamcop.net | www.fptech.com | #include <std_disclaimer.h> |
+-------------------------+--------------------+-----------------------------+

[James Stevenson]

SEGV - Tends to mean you have attempted to access a segment of
memory that does not exist.

BUS - Tends to mean you have attempted to access a segment of
memory that dies exist but have accessed it in correctly
sometimes certin cpu's require address to be aligned on certin
boundryies eg 8 / 16 / 32 / 64 bit address

Although this is offtopic it can cause havoc when trying
to write C programs on certin types of cpu's because of certin
alignment problems.

PS. i had to rewrite malloc / free / etc.. to get around this
problem on 1 system.

James

On 2 Aug 2004, junky_fellow wrote:

what is the difference between signals SIGBUS and SIGSEGV ?
when does an application program receive SIGBUS and in which
cases SIGSEGV ?

thanx in advance for any help ...

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