One of the tasks I want to do is to read/write from/to any physical address. My question is how do I get a physical address on my Linux desktop. I was thinking of using some utility to dump my BIOS settings, and modify a "not so important" memory address there? Is this possible. Otherwise is there any other physical address I can read/write
View 3 RepliesHow can I get the physical address corresponding to a virtual address in linux by using /proc file system
View 1 Replies View Relatedim REALLY new with linux and ive downloaded and installed Ubuntu...now heres the question.how do i set up WLAN internet use? ive tried using ipconfig/all on windows command but im not sure which info to use where save for the Physical Address going towards the MAC Address info
View 14 Replies View RelatedI need a small shell based program that prints the mac address of physical ethernet adapter from it's firmware. I need this utility for license generation and appliance activation. I have tried several example but none of them is flawless, The easiest method I have found is to parse the output of "ifconfig" command but it has also some drawbacks.
1. Firstly program should differentiate between physical and virtual adapters. Physical means installed on board(wired or wireless) or installed additionally. Virtual adapters are those created by VPN or created by virtualization apps such as VirtualBox/VMWare etc. I am not interested in virtual ones.
2. In case of more them one physical adapters(wired and wireless), it should print the mac address and description(name & vendor) of both/all adapters.
3. If media is disconnected then also it should be able to read the mac address and description(name, vendor) of card.
4. This one is bit complex. I know that 'ethtool' can show you the universal mac address but it's limited to use only 2 types of drivers and won't work in all cases.
I want to translate the virtual address to physical address in linux C application, how to do that?
View 1 Replies View RelatedA process is trying one access to memory, for example through an array (ex.: vect[0]=123. What happens?
Here below what I guess but I'm not sure and accept any comment (please, distinguish between "the system" and "the CPU" in case).
Let's suppose swapping to disk disbled.
We have two scenarios: without and with cache.
If no cache is present in the system:
1. The CPU must discover the phys addr of vect[0] virtual addr. To do that, has to read from 3 (or 2 depending on the system?) pages tables, stored in memory as well.
2. The CPU writes to the final address.
These mean 4 memory accesses.
If cache is present:
1. Like above but, if the pages tables are in cache, we have 3 accesses to that.
2. If the req. page is not in cache, it's reads from ram and transferred to it. Afterwards, cache is written.
In the best case we have 4 cache accesses.
When I try to access at physical address (0xD0000), we known that it is necessary to convert physical address to virtual address using function IOREMAP(0xD0000, 1024) and return me 0xC00D0000.
Now our doubt is when I have a board with I/O in address 0x150, is it necessary to convert this address to other virtual address??? or with inb(0x150) return me state of I/O in this address? How can I known where is this I/O address in my map memory?
As i undertsand - out of 1GB of the virtual Address space for Kernel from 3GB to 4GB of the process address space, Kernel image (code, data, bss, stack, heap) resides staring @0x0 address. Vmalloc area starts either at the end of Physical ram size or at 896M. This 896M cap is mandated to ensure that minimum of 128MB is reserved as vmalloc_reserve for vmalloc,kmap etc.
Is the understanding correct? Now trying to map Physical Zones into this 1GB address space
Initial 16MB is mapped to ZONE_DMA
16MB - 896MB is mapped to ZONE_NORMAL
896MB - 1024MB is mapped to ZONE_HIGHMEM
Does this mean that Kernel image is residing in ZONE_DMA area? Any call to vmalloc() in kernel code will return address beyond 896M? insmod of any LKM will internally invoke vmalloc() to obtain contiguous area - where will this code physically located along with rest of kernel code in ZONE_DMA or in ZONE_HIGHMEM?
how easy it would be to read the contents of a physical disk that was part of a larger logical volume. The disk contains a "Linux LVM" partition that spans its entire size. My problem is that one of my disks died, and I have to send it back for a warranty replacement. However, the disk is dead, and I can't zero it out. I'm just trying to assess how difficult it would be (or at least how likely it would be) for a tech that's checking out the disk to get at the data.
View 4 Replies View RelatedWhat are the possible problem when Windows access the file from Ubuntu got Read Only even though have a full permission to read, write and execute the file? Ubuntu to Ubuntu accessing the file there is no problem only Windows got a problem.
View 1 Replies View RelatedI have been given a headless linux system running from a SD card. I get into it by putty, directly to root, not other user and even /home dir. Whatever I copy or write will dissapear because is ro.
my etc/fstab file is:
none /dev/pts devpts gid=5,mode=620 0 0
none /proc proc defaults 0 0
none /dev/shm tmpfs defaults 0 0
/dev/hda1 /boot vfatnoauto,rw 0 0
how to read and write i.e setting of hardware clock through c program on linux
View 5 Replies View Relatedif i have a dir with several mp3's files:
example:
[root@xxx]ls -l
-rwxr-xr-x 1 web2 client1 6222573 Nov 26 17:34 01 Artist1 - Song1.mp3
-rwxr-xr-x 1 web2 client1 4989384 Nov 26 17:34 02 Artist2 - Song2.mp3
-rwxr-xr-x 1 web2 client1 6987438 Nov 26 17:36 03 Artist3 - Song3.mp3
and i need to update the id3 tag of all files with the command:
/usr/bin/id3v2 -a "Artist1" -t "Song1" Artist1 - Song1.mp3
how i do a loop to read the filename and execute the id3v2 command for each file, as i have filenames with spaces and special chars ex:"".
I am interested to know memory layout in linux os.What are the differences between physical address and virtual address?
View 1 Replies View RelatedHow do I get the page pointer from a physical address?
View 1 Replies View RelatedI am trying to write a C++ Code to read write a XML file in C++.I researched a lot and find xerces is used for that but I am not able to write the code for that.Please provide me some links on how to run a code that R/W a xml file in C++.
View 1 Replies View RelatedSuch as the title
View 2 Replies View RelatedAll my important data like ebooks and some programs are in a ntfs partition...when i login to my redhat i am unable to access that partition..
How to access(r/w) that partition in linux(Red Hat)?
I'm using Arch right now and i'm having problems syncing my ipod with Amarok (KDE). Everytime I would want to sync a song, it would give me access denied. it is currently mounted at /tmp/ipodbxQtrU and i have tried using chmod with no luck. I was in root when i used "chmod -R user ipodbxQtrU" and it said operation not permitted.
View 1 Replies View RelatedI've just arrived at uni and to set up my wifi apparently I need my "media access control which is listed as the phsyical address for ethernet adaptor local area connection." on windows you can find it by using the command ipconfig /all but that didn't work when i put it into terminal.
View 1 Replies View RelatedI have created directories in root. I am looking for the chmod command to allow all users read and write permissions to a specific directory. I have done chmod 775 for a file but I need this for a directory. This includes permissions on all files and sub directories.
View 3 Replies View RelatedWhat I want to be able to do, is have create a group, for example called "group1" and set its default permissions to read & write, instead of the usual just read.
So when I add a user into "group1" they automatically have read & write access to all files & directories which is in "group1".
Oh & I use crunchbang 10 (statler) for my desktops & Ubuntu 11.04 for my NFS/print/SSH/etc/etc server
I have a file the owner is root:root ( mode is 644 ), I want to release read & write permission to a non root user ( eg. admin_usr ), I tried to create a specific group ( eg. ADM ) and release it to root user and admin_usr ( by adding this users to ADM in /etc/group ) , but it is not work, if preserve the file mode to 644 , is it ok? how to do it if I want to have read & write permission in my case ?
View 5 Replies View RelatedI need to change a filename but when I boot up I get the message root device is read-only. Is there a way of changing this so that I can change the filename. I have a Mac Pro running Leopard OSX. The graphics card an NVIDIA 7500GT or driver has failed. It was suggested elsewhere that I change the relevant kext files to filename.kext.old, which I did, now when I try to boot start in OSX I get a message in various languages telling me to restart. I have tried booting in safe mode and from original Installation CD. In Safe Mode I get the same multi language splash screen, from CD I still have the graphic card problem, screen freezes and artifacts appear. So I boot up straight into CLI by holding down CMD-S hoping to be able to change filenames back but it says device read-only.
View 2 Replies View RelatedHow make, that disc be able to read and write data for all users? I have Ubuntu 9.
View 2 Replies View RelatedI installed fedora 12 and windows 7 in pc. i can not access fedora partitions from windows. which software is suitable for this?
View 8 Replies View RelatedI have a minilinux that I being working on, the problem now is that the serial ports doesn't seem to work (I have 4 serial ports).They don't write or read.
I run the command setserial g /dev/ttySx and it says that his IRQ are 3 or 4 (3 for ttyS0 and ttyS2 , 4 for ttyS1 and ttyS4)�but when I run the command: dmesg | grep ttyS the IRQ�s are 0 for ALL my serial ports� could be this the reason why my serial ports aren�t working right??? And if it is how can I solve the problem??
I allocated a chunk of memory using kmalloc in a Device Driver. Kmalloc provides a pointer to the allocated memory. This is one of my first few drivers.
I assume that the address returned is a Virtual address. I need to find the physical address of the memory location. I am working on an Intel 64 bit Fedora machine. I used the virt_to_phys() routine present in <asm/io_64.h>. I found that this routine returns an unsigned long value (32 bit) instead of an unsigned long long value (64 bit). Moreover, it seems that it simply returns the address - OFFSET instead of extracting the value in the page tables.
So is there any function / system call in Linux which will allow me to see the actual physical address on the Intel 64 arch.
How to printing physical address of page directories for all processes?
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
[code]....
I own a particular file on a Linux system. I would like to give 2 groups (accounting, shipping) read access and only read access, and 3 users(Mike, Raj and Wally) write access and only write access. How can I accomplish this?
View 3 Replies View Related