usr/src/local/sccscmds/sccscmds.2/util/setsig.c

# include       "signal.h"
#undef NSIG
# ifdef PWB
#define NSIG 16
# else
#define NSIG 4
# endif
# include       "../hdr/macros.h"
SCCSID(@(#)setsig       2.1);

/*
        General-purpose signal setting routine.
        All non-ignored, non-caught signals are caught.
        If a signal other than hangup, interrupt, or quit is caught,
        a "user-oriented" message is printed on file descriptor 2 with
        a number for help(I).
        If hangup, interrupt or quit is caught, that signal
        is set to ignore.
        Termination is like that of "fatal",
        via "clean_up(sig)" (sig is the signal number)
        and "exit(userexit(1))".

        If the file "dump.core" exists in the current directory
        the function commits
        suicide to produce a core dump
        (after calling clean_up, but before calling userexit).
*/


char    *Mesg[NSIG] {
        0,
        0,      /* Hangup */
        0,      /* Interrupt */
        0,      /* Quit */
# ifdef PWB
        "Illegal instruction",
        "Trace/BPT trap",
        "IOT trap",
        "EMT trap",
        "Floating exception",
        "Killed",
        "Bus error",
        "Memory fault",
        "Bad system call",
        "Broken pipe",
        "Alarm clock",
        "Terminated"
# endif PWB
};


setsig()
{
        extern int setsig1();
        register int j, n;

        for (j=1; j<NSIG; j++)
                if (n=signal(j,setsig1))
                        signal(j,n);
}


static char preface[]   "SIGNAL: ";
static char endmsg[]    " (ut12)\n";

setsig1(sig)
int sig;
{
# ifndef PWB
        sig = 2;
# endif PWB
        if (Mesg[sig]) {
                syswrite(2,preface,length(preface));
                syswrite(2,Mesg[sig],length(Mesg[sig]));
                syswrite(2,endmsg,length(endmsg));
        }
        else
                signal(sig,1);
        clean_up(sig);
        if(open("dump.core",0) > 0) {
                signal(SIGIOT,0);
                abort();
        }
        exit(userexit(1));
}