'\" te
.\" Copyright (c) 2008, Sun Microsystems, Inc.  All Rights Reserved.
.\" Copyright 1989 AT&T
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
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.TH siginfo.h 3HEAD "5 Feb 2008" "SunOS 5.11" "Headers"
.SH NAME
siginfo.h, siginfo \- signal generation information
.SH SYNOPSIS
.LP
.nf
#include <siginfo.h> 
.fi

.SH DESCRIPTION
.sp
.LP
If a process is catching a signal,  it might request information that tells why
the system generated that signal. See  \fBsigaction\fR(2). If a process is
monitoring its children, it might receive information that tells why a child
changed state. See  \fBwaitid\fR(2). In either case, the system returns the
information in a structure of type  \fBsiginfo_t\fR, which includes the
following information:
.sp
.in +2
.nf
int            si_signo        /* signal number */
int            si_errno        /* error number */
int            si_code         /* signal code */
union sigval   si_value        /* signal value */
.fi
.in -2

.sp
.LP
\fBsi_signo\fR contains the system-generated signal number. For the
\fBwaitid\fR(2) function,  \fBsi_signo\fR is always  \fBSIGCHLD\fR.
.sp
.LP
If  \fBsi_errno\fR is non-zero, it contains an error number associated with
this signal, as defined in  \fB<errno.h>\fR\&.
.sp
.LP
\fBsi_code\fR contains a code identifying the cause of the signal.
.sp
.LP
If the value of the  \fBsi_code\fR member is  \fBSI_NOINFO,\fR only the
\fBsi_signo\fR member of  \fBsiginfo_t\fR is meaningful, and the value of all
other members is unspecified.
.SS "User Signals"
.sp
.LP
If the value of  \fBsi_code\fR is less than or equal to 0, then the signal was
generated by a user process (see  \fBkill\fR(2), \fB_lwp_kill\fR(2),
\fBsigqueue\fR(3C), \fBsigsend\fR(2), \fBabort\fR(3C), and \fBraise\fR(3C)) and
the  \fBsiginfo\fR structure contains the following additional information:
.sp
.in +2
.nf
pid_t        si_pid      /* sending process ID */
uid_t        si_uid      /* sending user ID */
ctid_t       si_ctid     /* sending contract ID */
zoneid_t     si_zoneid   /* sending zone ID */S
.fi
.in -2

.sp
.LP
If the signal was generated by a user process, the following values are defined
for \fBsi_code\fR:
.sp
.ne 2
.mk
.na
\fB\fBSI_USER\fR \fR
.ad
.RS 15n
.rt  
The implementation sets \fBsi_code\fR to \fBSI_USER\fR if the signal was sent
by \fBkill\fR(2), \fBsigsend\fR(2), \fBraise\fR(3C) or \fBabort\fR(3C).
.RE

.sp
.ne 2
.mk
.na
\fB\fBSI_LWP\fR \fR
.ad
.RS 15n
.rt  
The signal was sent by \fB_lwp_kill\fR(2).
.RE

.sp
.ne 2
.mk
.na
\fB\fBSI_QUEUE\fR \fR
.ad
.RS 15n
.rt  
The signal was sent by \fBsigqueue\fR(3C).
.RE

.sp
.ne 2
.mk
.na
\fB\fBSI_TIMER\fR \fR
.ad
.RS 15n
.rt  
The signal was generated by the expiration of a timer created by
\fBtimer_settime\fR(3C).
.RE

.sp
.ne 2
.mk
.na
\fB\fBSI_ASYNCIO\fR \fR
.ad
.RS 15n
.rt  
The signal was generated by the completion of an asynchronous  \fBI/O\fR
request.
.RE

.sp
.ne 2
.mk
.na
\fB\fBSI_MESGQ\fR \fR
.ad
.RS 15n
.rt  
The signal was generated by the arrival of a message on an empty message queue.
See \fBmq_notify\fR(3C).
.RE

.sp
.LP
\fBsi_value\fR contains the application specified value, which is passed to the
application's signal-catching function at the time of the signal delivery if
\fBsi_code\fR is any of \fBSI_QUEUE\fR, \fBSI_TIMER\fR, \fBSI_ASYNCHIO\fR, or
\fBSI_MESGQ\fR.
.SS "System Signals"
.sp
.LP
Non-user generated signals can arise for a number of reasons. For all of these
cases, \fBsi_code\fR contains a positive value reflecting the reason why the
system generated the signal:
.sp

.sp
.TS
tab();
lw(1.24i) lw(1.74i) lw(2.53i) 
lw(1.24i) lw(1.74i) lw(2.53i) 
.
SignalCodeReason
_
SIGILLILL_ILLOPCillegal opcode
ILL_ILLOPNillegal operand
ILL_ILLADRillegal addressing mode
ILL_ILLTRPillegal trap
ILL_PRVOPCprivileged opcode
ILL_PRVREGprivileged register
ILL_COPROCco-processor error
ILL_BADSTKinternal stack error
_
SIGFPEFPE_INTDIVinteger divide by zero
FPE_INTOVFinteger overflow
FPE_FLTDIVfloating point divide by zero
FPE_FLTOVFfloating point overflow
FPE_FLTUNDfloating point underflow
FPE_FLTRESfloating point inexact result
FPE_FLTINVinvalid floating point operation
FPE_FLTSUBsubscript out of range
_
SIGSEGVSEGV_MAPERRaddress not mapped to object
SEGV_ACCERRinvalid permissions for mapped object
_
SIGBUSBUS_ADRALNinvalid address alignment
BUS_ADRERRnon-existent physical address
BUS_OBJERRobject specific hardware error
_
SIGTRAPTRAP_BRKPTprocess breakpoint
TRAP_TRACEprocess trace trap
_
SIGCHLDCLD_EXITEDchild has exited
CLD_KILLEDchild was killed
CLD_DUMPEDchild terminated abnormally
CLD_TRAPPEDtraced child has trapped
CLD_STOPPEDchild has stopped
CLD_CONTINUEDstopped child had continued
_
SIGPOLLPOLL_INdata input available
POLL_OUToutput buffers available
POLL_MSGinput message available
POLL_ERRI/O error
POLL_PRIhigh priority input available
POLL_HUPdevice disconnected
.TE

.sp
.LP
Signals can also be generated from the resource control subsystem. Where these
signals do not already possess kernel-level \fBsiginfo\fR codes, the
\fBsiginfo\fR \fBsi_code\fR will be filled with \fBSI_RCTL\fR to indicate a
kernel-generated signal from an established resource control value.
.sp

.sp
.TS
tab();
cw(1.19i) cw(1.65i) cw(2.65i) 
lw(1.19i) lw(1.65i) lw(2.65i) 
.
SignalCodeReason
_
SIGXRESSI_RCTLresource-control generated signal
_
SIGHUP
SIGTERM
.TE

.sp
.LP
The uncatchable signals \fBSIGSTOP\fR and \fBSIGKILL\fR have undefined
\fBsiginfo\fR codes.
.sp
.LP
Signals sent with a \fBsiginfo\fR code of \fBSI_RCTL\fR contain code-dependent
information for kernel-generated signals:
.sp

.sp
.TS
tab();
cw(1.19i) cw(1.65i) cw(2.65i) 
lw(1.19i) lw(1.65i) lw(2.65i) 
.
Code FieldValue
_
SI_RCTLhr_time si_entityprocess-model entity of control
.TE

.sp
.LP
In addition, the following signal-dependent information is available for
kernel-generated signals:
.sp

.sp
.TS
tab();
cw(1.19i) cw(1.67i) cw(2.64i) 
lw(1.19i) lw(1.67i) lw(2.64i) 
.
SignalFieldValue
_
SIGILLcaddr_t si_addraddress of faulting instruction 
_
SIGFPE
_
SIGSEGVcaddr_t si_addraddress of faulting memory reference
SIGBUS
_
SIGCHLDpid_t si_pidchild process ID
int si_statusexit value or signal
_
SIGPOLLlong si_bandT{
band event for \fBPOLL_IN\fR, \fBPOLL_OUT\fR, or \fBPOLL_MSG\fR
T}
.TE

.SH SEE ALSO
.sp
.LP
\fB_lwp_kill\fR(2), \fBkill\fR(2), \fBsetrctl\fR(2), \fBsigaction\fR(2),
\fBsigsend\fR(2), \fBwaitid\fR(2), \fBabort\fR(3C), \fBaio_read\fR(3C),
\fBmq_notify\fR(3C), \fBraise\fR(3C), \fBsignal.h\fR(3HEAD),
\fBsigqueue\fR(3C), \fBtimer_create\fR(3C), \fBtimer_settime\fR(3C)
.SH NOTES
.sp
.LP
For  \fBSIGCHLD\fR signals, if  \fBsi_code\fR is equal to  \fBCLD_EXITED,\fR
then  \fBsi_status\fR is equal to the exit value of the process; otherwise, it
is equal to the signal that caused the process to  change state. For some
implementations, the exact value of \fBsi_addr\fR might not be available; in
that case, \fBsi_addr\fR is guaranteed to be on the same page as the faulting
instruction or memory reference.