11-28-2008
SIGHUP only goes to the script you wrote when the terminal (with CLOCAL flag set) disconnects or if you send the script process itself a SIGHUP. The trap works in this case.
If SIGHUP is sent directly to the child process it terminates - for example with kill -HUP <pid>, your trap is not executed.
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
I am curious about HUP..... kill -HUP pid
What exactly does it do?? Does it stop the process and restart it from the beginning or from where it stopped? Thanks (6 Replies)
Discussion started by: jwbrown
6 Replies
2. UNIX for Dummies Questions & Answers
solaris can't support pkill command:( (2 Replies)
Discussion started by: cloudsmell
2 Replies
3. Linux
Hi All,
I modified /etc/syslog.conf and execute kill -HUP syslogd_PID. There's nothing changes on the PID when I did ps -ef|grep syslogd. It's the same. Do you think it restarted the process of syslogd?
Thanks in advance. (3 Replies)
Discussion started by: itik
3 Replies
4. Shell Programming and Scripting
Hi all
I have Master script, Main script ,and 4 Child script.
Master.sh
#!/bin/bash
/export/home/user/Main.shMain.sh
#!/bin/bash
/export/home/user/Child1.sh &
/export/home/user/Child2.sh &
/export/home/user/Child3.sh &
/export/home/user/Child4.sh &I run only Master.sh script... (1 Reply)
Discussion started by: almanto
1 Replies
5. UNIX for Dummies Questions & Answers
Hello - I need to know the detail of HUP and SEGV.
I know HUP is Hangup and can be use to kill a Unix login session remotely by sending a hangup signal to the process running the login session.
Could someone tell me in detail prupose of HUP and SEGV (segmentation violation)?
I need to... (1 Reply)
Discussion started by: namasteall2000
1 Replies
6. Shell Programming and Scripting
Hi
Is there any way to find out in a single step ( command) the step where the pipe command failed when using multiple commands using pipe .
eg : ll *.tar | grep dec | grep december.tar
the first step is listing all tar files . Second step constitutes piping that data and
doing grep... (5 Replies)
Discussion started by: ultimatix
5 Replies
7. Solaris
Hi,
I'm trying to provide "/usr/bin/kill -HUP" command to one of the user using sudo file. I have configured sudo as following:
$cat /etc/sudoers
User_Alias AA=conadmin
Cmnd_Alias KILL1=/usr/bin/kill -HUPAA ALL=NOPASSWD:KILL1
When I login as the user and execute 'sudo -l' command, it... (2 Replies)
Discussion started by: mohzub
2 Replies
8. UNIX for Advanced & Expert Users
Hi
In my program I have already used both SIGUSR1 SIGUSR2 user signals.
I need another one.
How can I do that?
Thank you
Naama (1 Reply)
Discussion started by: naamabm
1 Replies
9. UNIX for Dummies Questions & Answers
I have this code that doesnt do what it is suppose to do. It should block signal that I send while process is running. I press control+z while this process is running and it should be blocked but it isnt. When i press control+z it gives me this....
+ Stopped
When I change SIGTSP into SIGINT then... (5 Replies)
Discussion started by: joker40
5 Replies
10. Shell Programming and Scripting
Greetings. This is my first post in this forum; I hope y'all find it useful. One caveat: "Concise" is my middle name. NOT! :D
I am almost done with a shell script that runs as a daemon. It monitors a message log that is frequently written to by a database server but it it works my client will... (2 Replies)
Discussion started by: jakesalomon
2 Replies
trap(1) User Commands trap(1)
NAME
trap, onintr - shell built-in functions to respond to (hardware) signals
SYNOPSIS
sh
trap [ argument n [n2...]]
csh
onintr [-| label]
ksh
*trap [ arg sig [ sig2...]]
DESCRIPTION
sh
The trap command argument is to be read and executed when the shell receives numeric or symbolic signal(s) (n). (Note: argument is scanned
once when the trap is set and once when the trap is taken.) Trap commands are executed in order of signal number or corresponding symbolic
names. Any attempt to set a trap on a signal that was ignored on entry to the current shell is ineffective. An attempt to trap on signal 11
(memory fault) produces an error. If argument is absent all trap(s) n are reset to their original values. If argument is the null string
this signal is ignored by the shell and by the commands it invokes. If n is 0 the command argument is executed on exit from the shell. The
trap command with no arguments prints a list of commands associated with each signal number.
csh
onintr controls the action of the shell on interrupts. With no arguments, onintr restores the default action of the shell on interrupts.
(The shell terminates shell scripts and returns to the terminal command input level). With the - argument, the shell ignores all inter-
rupts. With a label argument, the shell executes a goto label when an interrupt is received or a child process terminates because it was
interrupted.
ksh
trap uses arg as a command to be read and executed when the shell receives signal(s) sig. (Note that arg is scanned once when the trap is
set and once when the trap is taken.) Each sig can be given as a number or as the name of the signal. trap commands are executed in order
of signal number. Any attempt to set a trap on a signal that was ignored on entry to the current shell is ineffective. If arg is omitted
or is -, then the trap(s) for each sig are reset to their original values. If arg is the null (the empty string, e.g., "" ) string then
this signal is ignored by the shell and by the commands it invokes. If sig is ERR then arg will be executed whenever a command has a non-
zero exit status. If sig is DEBUG then arg will be executed after each command. If sig is 0 or EXIT for a trap set outside any function
then the command arg is executed on exit from the shell. The trap command with no arguments prints a list of commands associated with each
signal number.
On this man page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Errors cause a script that contains them to abort.
4. Words, following a command preceded by ** that are in the format of a variable assignment, are expanded with the same rules as a vari-
able assignment. This means that tilde substitution is performed after the = sign and word splitting and file name generation are not
performed.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO
csh(1), exit(1), ksh(1), sh(1), attributes(5)
SunOS 5.10 23 Oct 1994 trap(1)