I would like to write a program that can read every ethernet frame arriving on a specific hardware NIC, without a TCP/IP stack otherwise doing anything on that NIC. Likewise I want to be able to write out to that NIC. So every arriving ethernet frame, of all types, would be readable (probably one at a time to preserve frame boundaries). And every write of exactly that same data would send frames out. The data read and written would be the whole ethernet frame. The kernel would do nothing else with this data, but other NICs would still operate as usual.
What I would be doing is that on 2 separate NICs, copying frames from one to the other, as in bridging. But I would also be doing modifications per what my program needs to do (not at liberty to say what that would be). What facility would I need to be looking at to do this? There is no ethernet device file. Would raw sockets be able to do this? The programming language will be C.
I am trying to read a file character wise and trying to write the same character to another file. In this process, I unable to read and write white spaces successfully to the new file. The script reads the white spaces but while writing the white space is lost. The section of the code, is given below. Please advice how can i read and retain the white space while writing to a new file.
Code:
if [ -s f_test.txt ] && [ -f f_test.txt ]; then echo "File Exists !!" while read -n1 char; do
There is the Archive::Zip I think I can use with Perl 5.10 but I don't know how. I don't want to read or write any files, just zip something in memory, with best compression, like
$text = "this is a test"; $zippedtext = &Zip($text); sub Zip {
Here the description of the issue I am having.I am writing a bash test script which reads lines from a file, builds ISO messages, sends them to a server, reads the response with response code and reports the result of the test to a file or on the screen.The message that I need to send is 94 characters long.Here's the portion of a code that I initially wrote:
~ Open socket. exec 3<>/dev/tcp/172.26.0.25/9991 #~ Send msg.
I am developing a GPS driver which is connected over a high speed UART. The driver of the high speed UART is available and it creates a device node /dev/ttyHS0. Now using the device node, I guess, I will be able to read/write from/to the GPS chip from user space but my aim is to write a GPS driver in the kernel space which would communicate with the high speed UART driver. After some initial study, I think I can either write a line discipline driver or a serio to communicate with the GPS chip firmware through high speed UART driver.
I want to modify ioctl TIOCMWAIT to return the same thing that ioctl TIOCMGET returns. Currently wait returns an int of zero or -1 when a change in status occurs. Why not make it return the new status?
This will make the operation faster by not requiring another call to ioctl.The extra call requires 2 to 16 uSeconds to complete on my x64 laptop. How would I make this proposal to the kernal people?
I've been able to get access to our Netgear NAS, I can browse it, copy files etc. just fine. But I don't have "direct access" in as far as, Open Office won't open any files residing on the NAS, neither can I save directly to the NAS form a program and when I get a "Browse for File" form field on a website (eg attachments in GMail etc.), I can't browse to the NAS either. My XP box does do all of this, either through my mapped network drive or even through browsing the network. How can I make openSuse 11.2 use the NAS with my login credentials as if it was a local disk?
I've used ext2ifs drivers to mount my ext3 partition in winxp, but I don't have write acces, it's mounted in a read-only mode, and i didn't check the rad-only box during the installation of the drivers. [URL] It's a straithfoward proces so I dont understand what I did wrong. I'm using fresh xp install with (more or less) all the updates and ubuntu 10.04 Also the partition is mounted at /home, so I dont know if that makes any difference.
I've used ext2ifs drivers to mount my ext3 partition in winxp, but I don't have write acces, it's mounted in a read-only mode, and i didn't check the rad-only box during the installation of the drivers.I've used help from the official site http://www.fs-driver.org/and this tutorial http://www.dedoimedo.com/computers/l...s-windows.html It's a straithfoward proces so I dont understand what I did wrong.I'm using fresh xp install with (more or less) all the updates and ubuntu 10.04Also the partition is mounted at /home, so I dont know if that makes any diferance.
My main workstation incorporates a mixture of ext3, ext4, and NTFS partitions scattered across a number of hard drives. Several of the ext4 partitions are encrypted, and I intend to encrypt the rest of the Linux partitions in the near future.I run VMware workstation, with several Windows OS guests, including Win2K, WinXP and Win7. My Win7 VM is installed on a virtual hard disk, and that virtual hard disk is encrypted using VMware facilities.So this leaves me with a bunch of NTFS partitions that are not encrypted. These are physical partitions on a couple of different hard drives. The reason I have them is ancient and historical, and as I have upgraded my system over time I have maintained the architecture due to the extreme difficulty of rearranging Windows systems.I still need to maintain Win2K and WinXP support, and rearranging those virtual machines would represent a hideous nightmare for me; I really want to maintain the same hard drive partition architecture.But I want to encrypt the NTFS partitions, in a fashion that can be handled by any of the Windows operating systems, AND can be accessed for read and write from Linux.Is this possible? If not using Windows facilities (I don't think ntfs-3g handles encryption, and there are known backdoors in the Windows facilities anyway), is there any third party solution that would work? Would True Crypt do the job in a fashion that would permit access from all the various operating systems, as required? I do generally mount the NTFS partitions in whichever Windows VM is appropriate, then share them out via SMB, but there are circumstances (like when a VM is not running) where I will directly hit them from Linux. So, it is possible for me to contemplate a solution that only works from Windows, but this would cost me the ability to repair/modify those filesystems directly from Linux, which under certain circumstances (a malfunction of the VM, for instance) could be a problem.
I am about to write a program to listen and read data from /dev/ttyS0 and write the data to /dev/ttyS1 after processing. Also, the same time I need to listen to /dev/ttyS1 and write to /dev/ttyS0 if any data arrived at /dev/ttyS1.
I want to be able to access my email account from the console. I'm reading all day about fetchmail, postfix, sendmail etc. but all the stuff I found is related to building whole mail system. All I want to do is to read my emails and write some. Which is the painless way to do this? I successfully configured Evolution for this purpose but I want to do that from the console.
At times I see heavy hard-disk activity slowing down system.I have enough RAM and enough of it free.Apparently I am not doing anything that should cause this.'vmstat' shows high numbers for "bi bo" I want to find out which processes are doing "bi bo".How can I zero in on the particular processes?What command?
Samba seems to crash and come back after some seconds if I copy a lot of small files in a short period of time over the network. How do I fix it?
I have Ubuntu 9.10 Server 64bit running on a D945GCLF2 board sharing two 1TB ext4 formatted HDDs to my Windows PCs using samba. I've been having an issue with reading or writing files through samba. It happens during copying operations or checksumming, anything that reads or writes MANY small files in a small amount of time. I am pretty sure the problem has to do with my server because the server has run on two different LANs in different homes and will crash from activity with any of several other PCs. There is no crashing if I access the files through SSH, although when I do that the max transfer speed is less than 1MB/s.
When I induce the crashing, there is absolutely no output to the server terminal.
As an easy access example of something that will crash samba, extracting Cinebench R11.5 to the server will do the job. It always fails.
Whenever I am busy reading or writing large files, or large sum of files, my computer is unresponsive. Screens are getting greyed-out and I just can sit there and wait until the reading/writing is done. This is not caused by the CPU which is overstressed because it is not. Look at the attachments and you will see the CPU is used for about 20%. When these pictures were captured the computer was using hellanzb to unrar a long list of rar-files. When you look at my signature you see the computer is not bad at all, just disk-access is slow. I can transfer files with a maximum speed of 30MB/s. Is that normal or is it very slow? I don't know the numbers. I have 2 SATA disks. O.S. is Mint 9-Isadora, based on Ubuntu 10.04 and I use the 64-bits version.
Am interested in using MT29F2G08AABWP NAND Flash memory for a new embedded design and I couldn�t find a clear specification regarding how reliable is the NAND flash vs. NOR for reading operation.If I program successfully a NAND block, read back and verify successfully the information and never erase or program that particular block again, can I assume that block will remain a good block and the information written there is safe for READING, roughly as safe as a NOR sector?
I synthesized a seismogram by using Fortran codes, I need plot the synthesized seismogram and the data together, so I can verify the accuracy of code. Now I encounter a question: how to read the SAC data by Fortran code, I have searched some codes on Internet, the details as follow:the velr12a.sac is my data file.
Code: c read sac file PROGRAM RSAC PARAMETER (MAX=1000) DIMENSION YARRAY(MAX) CHARACTER*10 KNAME
On a Linux CD/DVD, there are compressed filesystem images for the live version for KDE or Gnome for example, but they have no extension, but they are clearly an image file ( compressed filesystem images for the live version before installation ) !!
I was wondering, How do I mount these compressed filesystem images, after I copy the ISO content of the CD/DVD on my system .... I want to edit some files or packages and make some changes, like if I want to customize a live version of gnome for example ! ... ( I know you might be tempted to tell me to use KIWI etc to customize etc ..... ) ... but I want to be able to mount the compressed file system image, then edit it for reading and writing while it is in a subdirectory on its own ... i want to open it ! ... is there a way to do this ??? ... these type of files have no extension ...
i can open this compressed filesystem image then to edit for read & write ... before I roll it back again ..... If and when I succeed .... what should I watch out for ? ... will the same compressed file image but slightly modified work again ?
PS. that same question could be kind of translated or be extended like : how do I use unionfs/squashfs programs on the command line to mount these image files with no extension for read & write mode ???
I'm creating a usb device driver that needs to be able to read from two different endpoints. I couldn't see any way of having two read functions in the driver, so I got round this by reading from one of the endpoints with read, and the other with ioctl.However this hasn't worked, the ioctl call from c returns -1. I added a printk command in the driver in the ioctl function, however looking at kern.log I can see that this function is never being called. Does anyone have any ideas as to what the problem called be, or a better method of being able to read from two different endpoints?
I use ioctl to get the console window size (the SSH window). I use the following code: struct winsize ws; int returnValue = ioctl(pCommandStructure->terminal, TIOCGWINSZ, &ws); int numberOfColumnsOfTerminalWindow = ws.ws_col; When I debug on linux pc, it gives me the correct window width. But after I try it on router (this is my enventual place where my code shall run), ioctl always give me 0 width, that is, numberOfColumnsOfTerminalWindow == 0. but the returnValue is 0 which means that the function call succeeds.
I am having the following problem. The following code works fine on my P.C. Ubuntu x64, and on a jetway mini-itx board with an atom processor. The problem is, the same code doesn't work on the intel equivalent of the jetway board. I thought the maybe, I didn't have the port configured right, so I turned on Hardware Flow control and also tried turning on the modem bits I needed with TIOCMBIS. Neither worked. Here is the code. There are two threads, one of them, respsponding to the client, and using the RTS and DTR pins to power two relays. The other, manages listening to CTS and DSR for input. Here is the class with the first thread.
Code:
/* * DigitalIOCore.cpp * * Created on: Nov 1, 2010 * Author: jonathan
I use ioctl to get the cosole window size (the SSH window).
I use the following code:
When I debug on linux pc, it gives me the correct window width. But after I try it on router (this is my enventual place where my code shall run), ioctl always give me 0 width, that is, numberOfColumnsOfTerminalWindow == 0. but the returnValue is 0 which means that the function call succeeds.
