General :: Find The Sequence For Signal Handling Mechanism In Kernel?
Apr 28, 2011
I am working on tracing the signal handling mechanism in linux kernel internallly. For that, i build the kernel. Now, i want to trace the signal handling mechanism in the old kernel. I got to about SYSLOG and PRINTK for this. But, how to use these tools exactly in tracing the handling of signals internally ?. Is, there any tool similar to backtrace to do that?. How the call flow is done internally ?
I have 4 Linux machines with cluster.My target is to find all kind of IP address (xxx.xxx.xxx.xxx) in every file in the linux system remark: need to scan each file in the linux system and verify if the file include IP address if yes need to print the IP as the following
I have created a pthread, and installed a signal handler inside that, same way as we do in main( ) function. The thread's signal handler is a separate function. Surprisingly, it is not working, that is the thread's signal handler is not able to catch signals. Here is the code:
I am currently working on "Creation of Postmortem data logger in Linux on Intel architecture. Its nothing but core utility creation. how the signal handlers for various signals(SIGSEGV,SIGABRT,SIGFPE etc) which produce core dump upon crashing an application internally implemented in Linux kernel. I need to re-write these signal handlers with my own user specific needs and rebuild the kernel. It makes my kernel producing the core file (upon crashing an application) with user specific needs like showing registers,stackdump and backtrace etc.
In a single main() function,so need signal handling. Use Posix Message Queue IPC mechanism , can ignore the priority and other linked list message,to implement the scenario:
Is there any Kernel parameter available for interrupts handling, In the case of busy server how we can tune the kernel to handle interrupts effectively.
i had a problem with the find command in bash (which i deem is close enough to a promming language, if not please move this thread :P). i tried to reduce the command to the problem. i want the backticks, or $() for that matter; to be evaluated by -exec of find, not by bash. is that a caveat of find?
Code:
$ find testd -exec echo `basename {}` ; #confused me test test/a test/b
[code]...
edit: i found out whats causing this. `basename {}` gets evaluated by bash before find is invoked, returns {} and `find . -exec echo {} ;" is run. now my question is, how to escape this eveluation from happening before.
Fedora Core 12 I must be going mad, but I thought I used to use a command such as:
grep -r ^[a-z] *|grep .....
to do a recursive search to find all files that had lines starting with lower case a to z.
If I try that under FC12 (this is a newish install), it also finds uppercase A to Z.
Is there a collating type sequence or locale that I have incorrectly set?
PS just for info, the following shows the problem: (Linux)retsol610 :stevet : /home/stevet> echo ABC |grep ^[a-z] ABC (Linux)retsol610 :stevet : /home/stevet> echo abc |grep ^[A-Z]
[code]....
ie the whole range matching seems a bit 'screwy'. A-z should give x01-x58 so A-z should be be valid and include a couple of spcial chars - but gives a range error. On the other hand, a-Z should pose a problem as that's a backward range - but that seems to search ok.
Does any one else get this in FC12 (I've just tried in RH EL5 and grep ^[a-z] ... works fine)? My locale is:
I am trying to setup a debian sid on my Chromebook (Asus C201 / Rockchip ARM).I've followed the howto here : URL.....Debootstrap ok, config ok, kernel repack ok... everything went fine until the first boot.When i boot from the sd card, nothing seem to happen. The screen stay black, no text appear.Back in chromeos, i check the syslog and the kernel did load successfully.
It seems after the kernel loads, nothing happen next.
Kernel is on mmcblk1p1 Rootfs is on mmcblk1p2 My kernel config is : Code: Select allconsole=tty1 printk.time=1 nosplash rootwait root=/dev/mmcblk1p2 rw rootfstype=ext2 lsm.module_locking=0
i want to know, what is vpath mechanism in makefile?i did google search this,but i couldn't understand it as i am beginner in linux os. or either give me few simple links related to vpath mechanism.
I have a general question and decided to post it here. Hopefully, I have picked a correct category. The thing I have been trying to figure out is the syn-cache mechanism. I know that it used to be utilized as a method to mitigate the impact of (D)DoS attacks. I would like to know what happened with it? Is it still added to the Linux systems? Perhaps I am missing something, and cannot find the correct man page about it. Is it the thing, that it is only for NetBSD project?
When using RPM/YUM or any other package manager, is the old version of that program deleted and then follow by an installation of the latest update? example:
nautilus-2.16.2-7.el5 update to nautilus-2.91.6-3.el5
will nautilus-2.16.2-7.el5 be uninstalled and then follow by an installation of nautilus-2.91.6-3.el5?
I use the on-board sound chip of a Gigabyte motherboard (Realtek)and I have connected it with optical cable to an amplifier.
Everything worked fine, until February, when an update changed the kernel and the PC stopped giving sound signal! When I returned to the previous kernel (at grub), again everything worked. So,it doesn't seem to be a connection or drivers problem.
I supposed that with 11.04 edition this problem would be solved. But it isn't. In fact I have serious problem now because the old kernel isn't listed in grub anymore.
But, if there is : symbol which separate namespace from action problems coming:
symfony doct[TAB] will be completed to symfony doctrine:
But nothing happens if you want complete after : symbol. I've found out that for readline there is three words because it splits line with $COMP_WORDBREAKS
Code:
$ echo $COMP_WORDBREAKS "'><=;|&(:
I played with $COMP_WORDS array and tried every thought I had to make it work, but failed. What I should do to escape colon and make readline consider it as one word? Or there is way perhaps to workaround it?
I am developing a device that will run Linux as its operating system.The device is a small form factor X86 device with a flash drive exposed as a SATA-device. So it is not very dissimilar from any other PC running Linux.For several good reasons I am building my own "distribution", instead of using an existing one.What confuses me is how mount/umount of the root file system is handled.I boot my kernel with the commandline "root=/dev/sda1 rw" which works fine. But everytime I do poweroff or reboot Busybox complained about no /etc/fstab, so I decided to build one.Should I have an entry for my root file system? It seems like this is shadowed by the rootfs anyway. I.e. if I have the fstab entry "/dev/sda1 / ext2 1 1" mount still reports rootfs on / type rootfs (rw)/dev/root on / type ext2 (rw,relatime,errors=continue)My questions are:Do I need to worry? Will the drive be correctly unmounted by the kernel on poweroff/reboot?If I want to perform file system checking on boot, can I do that without resorting to an initrd?
I want to run a script when the switch goes down and an other when it goes up. Is there an easy way to pull this off in Debian (preferably with no other than system tools)? I suppose there is no difference (in the OS point of view) between unplugging ethernet cable and the switch losing power.
On an event I get lines like these in the syslog: Jun 15 17:49:41 debian kernel: [ 5506.956130] igb: eth1 NIC Link is Down ... Jun 15 17:49:45 debian kernel: [ 5511.168788] igb: eth1 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
In FreeBSD you can pipe log messages (pre-filtered by regex patterns) to a program. What is the easiest way to replicate this on Debian (with as little additional software as possible)?
after installing Debian 6 on a server. When I try to install a software called ActiveCampaign, I get the following error ... "Your server does not appear to be handling sessions properly."I have install Apache, PHP, MySql and Perl already. Also, after the server restarts, I Webmin will not automatically start, even thou it is setup in the Webmin configuration to start with the server. I have to use /etc/init.d/webmin start from a command line after I su.
My last question is about ftp permissions. I have install proftpd and it seems to be working fine, but when I try to edit any file or upload, I can not. In order to upload and manipulate files, I am using WinSCP under root, wich is a big NO NO.Sorry for the three questions, but I figured I would ask all in one post, instead of creating multiple, since I already have your attention.
Pretty soon, I hope, I'll get my brand new PC and wish to install a Linux disto. on it. openSuse may be it But I read recently that people prefer to do a fresh install of a newer version of openSuse, instead of upgrading it, apparently because of problems that may occur by the upgrade. As I understand, this preference apply to all Linux distributions and not only openSuse. Thus I wonder if there's a Linux distro. that's best in handling upgrades?I don't want to make a fresh new install each and every time that my disro. has a new version. I'm afraid to lose the data in that installation, and backing-up the data would be a headache. Also I plan to install a Windows OS alongside the Linux one via the Dual Boot configuration.
I compiled my own kernel with tun/tap and bridge support. Both modules load fine at boot time (I could read that in the dmesg output). Now I want to use it, and the /dev/net/tun node is not there, so my application gives that error. I'm trying to bridge openvpn connections. Is it possible that udevd is not doing his work?
PS: I'm on a WD MyBook World Ed NAS device. It's ARM, so I cross compiled the kernel from my debian linux machine. I also installed debian on the NAS.)
I'm currently trying to get my wireless card to work with ndiswrapper after installing backtrack4 today, BUT.When I try and use the make command it tells me that some or another file is missing. I've checked and the output is right, There is no file of that name but there is neither a folder of that name.
Code:
root@bt:/usr/src/ndiswrapper-1.56/ndiswrapper-1.56# make make -C driver make[1]: Entering directory `/usr/src/ndiswrapper-1.56/ndiswrapper-1.56/driver'
I just downloaded the newest version of Ubuntu onto a USB drive. I put it into my computer and when it was loading Ubuntu, it said "Could not find kernal image: vesamenu.c32".
