abort.3: Clarify consequences of calling abort()

Clarify that atexit(3)/on_exit(3) are not called because those are
called only on normal process termination (as documented on their
respective manual pages).

Check with the following test program:

```c
 #define _DEFAULT_SOURCE

 #include <stdio.h>
 #include <stdlib.h>

void one(void)
{
    puts("atexit called");
}

void two(int, void*)
{
    puts("on_exit called");
}

int main(void)
{
    atexit(one);
    on_exit(two, NULL);

    puts("terminating");
    //abort();
    exit(EXIT_SUCCESS);
}
```

Cc: "G. Branden Robinson" <g.branden.robinson@gmail.com>
Cc: Stefan Puiu <stefan.puiu@gmail.com>
Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/man3/abort.3 b/man3/abort.3
index 0b57e10ed..a466d0913 100644
--- a/man3/abort.3
+++ b/man3/abort.3
@@ -47,6 +47,12 @@ function will still terminate the process.
 It does this by restoring the default disposition for
 .B SIGABRT
 and then raising the signal for a second time.
+.PP
+As with other cases of abnormal termination the functions registered with
+.BR atexit (3)
+and
+.BR on_exit (3)
+are not called.
 .SH RETURN VALUE
 The
 .BR abort ()