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Full Discussion: Use of TRAP Command
Top Forums Shell Programming and Scripting Use of TRAP Command Post 302099416 by vino on Tuesday 12th of December 2006 02:56:31 AM
Old 12-12-2006
Quote:
Originally Posted by Deepakh
Also i would like to know the use of following command:

trap 'dialog --msgbox "Script Aborted1" 6 50 ; error exit' 1 2 3 15..

Please let me know wat the numbers shown in the above example does mean??
trap is a shell builtin which executes the command when the shell receives signals. In your example, the command would translate to 'dialog --msgbox "Script Aborted1" 6 50 ; error exit'. The signals translates to 1, 2, 3 and 15.

Hence whenever your script receives any of the signal 1, 2, 3 or 15, then a popup comes up with the message "Script Aborted1" and the script exits.

From man 7 signal, this is what the numbers stand for
Code:
       Signal     Value     Action   Comment
       -------------------------------------------------------------------------
       SIGHUP        1       Term    Hangup detected on controlling terminal
                                     or death of controlling process
       SIGINT        2       Term    Interrupt from keyboard
       SIGQUIT       3       Core    Quit from keyboard
       SIGILL        4       Core    Illegal Instruction
       SIGABRT       6       Core    Abort signal from abort(3)
       SIGFPE        8       Core    Floating point exception
       SIGKILL       9       Term    Kill signal
       SIGSEGV      11       Core    Invalid memory reference
       SIGPIPE      13       Term    Broken pipe: write to pipe with no readers
       SIGALRM      14       Term    Timer signal from alarm(2)
       SIGTERM      15       Term    Termination signal
       SIGUSR1   30,10,16    Term    User-defined signal 1
       SIGUSR2   31,12,17    Term    User-defined signal 2
       SIGCHLD   20,17,18    Ign     Child stopped or terminated
       SIGCONT   19,18,25            Continue if stopped
       SIGSTOP   17,19,23    Stop    Stop process
       SIGTSTP   18,20,24    Stop    Stop typed at tty
       SIGTTIN   21,21,26    Stop    tty input for background process
       SIGTTOU   22,22,27    Stop    tty output for background process

The signals SIGKILL and SIGSTOP can not be trapped.
 

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LEARN ABOUT SUSE

snmpinform

SNMPTRAP(1)							     Net-SNMP							       SNMPTRAP(1)

NAME

       snmptrap, snmpinform - sends an SNMP notification to a manager

SYNOPSIS

       snmptrap -v 1 [COMMON OPTIONS] [-Ci] enterprise-oid agent generic-trap specific-trap uptime [OID TYPE VALUE]...

       snmptrap -v [2c|3] [COMMON OPTIONS] [-Ci] uptime trap-oid [OID TYPE VALUE]...

       snmpinform -v [2c|3] [COMMON OPTIONS] uptime trap-oid [OID TYPE VALUE]...

DESCRIPTION

       snmptrap is an SNMP application that uses the SNMP TRAP operation to send information to a network manager.  One or more object identifiers
       (OIDs) can be given as arguments on the command line.  A type and a value must accompany each object identifier.   Each	variable  name	is
       given in the format specified in variables(5).

       When  invoked  as snmpinform, or when -Ci is added to the command line flags of snmptrap, it sends an INFORM-PDU, expecting a response from
       the trap receiver, retransmitting if required.  Otherwise it sends an TRAP-PDU or TRAP2-PDU.

       If any of the required version 1 parameters, enterprise-oid, agent, and uptime are specified as empty,  it  defaults  to  1.3.6.1.4.1.3.1.1
       (enterprises.cmu.1.1), hostname, and host-uptime respectively.

       The TYPE is a single character, one of:
	      i  INTEGER
	      u  UNSIGNED
	      c  COUNTER32
	      s  STRING
	      x  HEX STRING
	      d  DECIMAL STRING
	      n  NULLOBJ
	      o  OBJID
	      t  TIMETICKS
	      a  IPADDRESS
	      b  BITS
       which are handled in the same way as the snmpset command.

       For example:

       snmptrap -v 1 -c public manager enterprises.spider test-hub 3 0 '' interfaces.iftable.ifentry.ifindex.1 i 1

       will send a generic linkUp trap to manager, for interface 1.

OPTIONS

       snmptrap takes the common options described in the snmpcmd(1) manual page in addition to the -Ci option described above.

SEE ALSO

       snmpcmd(1), snmpset(1), variables(5).

4th Berkeley Distribution					    08 Feb 2002 						       SNMPTRAP(1)
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