SIGINFO(2)						      BSD System Calls Manual							SIGINFO(2)

NAME

     siginfo -- signal information

SYNOPSIS

     #include <signal.h>

DESCRIPTION

     siginfo is a structure type which contains information about a signal delivered to a process.

     siginfo includes the following members:

	   int si_signo;
	   int si_errno;
	   int si_code;

     si_signo contains the signal number generated by the system.

     If si_errno is non-zero, then it contains a system specific error number associated with this signal.  This number is defined in errno(2).

     If si_code is less than or equal to zero, the signal was generated by a user process or a user requested service:

     SI_USER	 The signal was generated via kill(2).	The siginfo structure contains the following additional members:

		       pid_t si_pid;
		       uid_t si_uid;

		 The si_pid field contains the pid of the sending process and the si_uid field contains the user id of the sending process.

     SI_TIMER	 The signal was generated because a timer set by timer_settime(2) has expired.	The siginfo structure contains the following addi-
		 tional members:

		       sigval_t si_value;

		 The si_value field contains the value set via timer_create(2).

     SI_ASYNCIO  The signal was generated by completion of an asynchronous I/O operation.  The siginfo structure contains the following additional
		 members:

		       int si_fd;
		       long si_band;

		 The si_fd argument contains the file descriptor number on which the operation was completed and the si_band field contains the
		 side and priority of the operation.  If the operation was a normal read, si_band will contain POLLIN | POLLRDNORM; on an out-of-
		 band read it will contain POLLPRI | POLLRDBAND; on a normal write it will contain POLLOUT | POLLWRNORM; on an out-of-band write
		 it will contain POLLPRI | POLLWRBAND.

     If si_code is positive, then it contains a signal specific reason why the signal was generated:

     SIGILL

	      ILL_ILLOPC  Illegal opcode

	      ILL_ILLOPN  Illegal operand

	      ILL_ILLADR  Illegal addressing mode

	      ILL_ILLTRP  Illegal trap

	      ILL_PRVOPC  Privileged opcode

	      ILL_PRVREG  Privileged register

	      ILL_COPROC  Coprocessor error

	      ILL_BADSTK  Internal stack error

     SIGFPE

	      FPE_INTDIV  Integer divide by zero

	      FPE_INTOVF  Integer overflow

	      FPE_FLTDIV  Floating point divide by zero

	      FPE_FLTOVF  Floating point overflow

	      FPE_FLTUND  Floating point underflow

	      FPE_FLTRES  Floating point inexact result

	      FPE_FLTINV  Invalid Floating point operation

	      FPE_FLTSUB  Subscript out of range

     SIGSEGV

	      SEGV_MAPERR  Address not mapped to object

	      SEGV_ACCERR  Invalid permissions for mapped object

     SIGBUS

	      BUS_ADRALN  Invalid address alignment

	      BUS_ADRERR  Non-existant physical address

	      BUS_OBJERR  Object specific hardware error

     SIGTRAP

	      TRAP_BRKPT  Process breakpoint

	      TRAP_TRACE  Process trace trap

     SIGCHLD

	      CLD_EXITED     Child has exited

	      CLD_KILLED     Child has terminated abnormally but did not create a core file

	      CLD_DUMPED     Child has terminated abnormally and created a core file

	      CLD_TRAPPED    Traced child has trapped

	      CLD_STOPPED    Child has stopped

	      CLD_CONTINUED  Stopped child has continued

     SIGPOLL

	      POLL_IN	Data input available

	      POLL_OUT	Output buffers available

	      POLL_MSG	Input message available

	      POLL_ERR	I/O Error

	      POLL_PRI	High priority input available

	      POLL_HUP	Device disconnected

     For SIGILL, SIGFPE, and SIGTRAP the siginfo structure contains the following additional members:

	   void *si_addr;
	   int si_trap;

     si_addr contains the address of the faulting instruction and si_trap contains a hardware specific reason.

     For SIGBUS and SIGSEGV the siginfo structure contains the following additional members:

	   void *si_addr;
	   int si_trap;

     si_addr contains the address of the faulting data and si_trap contains a hardware specific reason.

     For SIGPOLL the siginfo structure contains the following additional members:

	   int si_fd;
	   long si_band;

     The si_fd argument contains the file descriptor number on which the operation was completed and the si_band field contains the side and pri-
     ority of the operation as described above.

     Finally, for SIGCHLD the siginfo structure contains the following additional members:

	   pid_t si_pid;
	   uid_t si_uid;
	   int si_status;
	   clock_t si_utime;
	   clock_t si_stime;

     The si_pid field contains the pid of the process who's status changed, the si_uid field contains the user id of the that process, the
     si_status field contains a status code described in waitpid(2), and the si_utime and si_stime fields contain the user and system process
     accounting time.

STANDARDS

     The siginfo type conforms to X/Open System Interfaces and Headers Issue 5 (``XSH5'').

HISTORY

     The siginfo functionality first appeared in AT&T System V Release 4 UNIX.

BSD
								   July 26, 2010							       BSD