Programming :: Multithreaded Reading And Writing Of A Shared Integer?
Nov 4, 2010It it safe to read a shared integer while another thread is writing to it on a multicore system?
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Programming :: Reading And Writing Text Files In C?
Jan 1, 2011Reading and writing text files in C?
View 9 Replies View RelatedProgramming :: Reading/writing Every Frame On Ethernet?
Dec 3, 2010I 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.
Programming :: Writing And Reading Driver Value In Ioctl?
Jan 18, 2011I just want to read and write some values (integer) to my driver. I used put/get user but always getting errors.
driver
Quote:
int Wert;
static int device_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsinged long arg)
int ret;
[code]...
Quote:
int WERT
ret=ioctl(fd, SETIT, WERT)
ret=ioctl(fd, GETIT, WERT)
if i say in C++ WERT is 5 the value arg of the driver becomes 5 but not WERT the returnvalue of get and put user is -1 so it failed.
Programming :: Reading And Writing White Spaces To A File?
Dec 2, 2010I 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
[code]....
Programming :: Zip A Variable With PERL Without Reading Or Writing A File?
Jun 20, 2010There 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 {
[code]...
I guess it's only a few lines.
Programming :: Writing To And Reading From A Socket From Bash Script?
Mar 11, 2010Here 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.
[code]...
Programming :: Line By Line Reading And Writing In Bash?
Nov 29, 2010I have a text file (myfile.txt) with columns a,b,c.
123 2 23
124 2 24
125 2 22
[code]...
Programming :: Multithreaded App Using Pth Does Not Work?
Mar 4, 2010I threw this togher based on the examples but the thread does not seem to run:
Code:
#include <stdio.h>
#include <pth.h>
[code]...
Programming :: MultiThreaded Program In C++?
Oct 23, 2010I have a program called "Device Manager" to manange usb tokens for sending and recieving
multiple data to/from them using shared memory method.Here is a piece of "Device Manager" code:
Code:
int main()
{
[code]...
Programming :: Debugging Multithreaded Application?
Aug 23, 2010i need to debug a application which is using many threads. i am using eclipse with GDB debugger but it is not possible to debug it since it has a lot of different threads and i can not not debug it as wre debug in case of single thread(main) . So i would like to know, is there a way to debug such an application, if there is some tutorial that would be nice to know.
View 8 Replies View RelatedGeneral :: Dd Gets Slower While Reading And Writing?
Jan 25, 2011user@user-laptop:~$ sudo dd if=sd_backup of=/dev/sdd bs=4M conv=noerror,sync
205520896 bytes (206 MB) copied, 28.564 s, 7.2 MB/s
247463936 bytes (247 MB) copied, 57.1285 s, 4.3 MB/s
260046848 bytes (260 MB) copied, 73.2388 s, 3.6 MB/s
289406976 bytes (289 MB) copied, 104.121 s, 2.8 MB/s
[Code]....
How come dd gets slower after copying this 8GB file? What can I do about it?
OpenSUSE Network :: Direct NAS Reading And Writing?
Feb 9, 2010I'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?
View 4 Replies View RelatedUbuntu :: Reading/writing Ext3 Partition From XP?
May 9, 2010I'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.
View 1 Replies View RelatedGeneral :: Reading/writing Ext3 Partiton From XP?
May 9, 2010I'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.
Security :: Reading/writing Encrypted NTFS?
Jul 25, 2010My 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.
View 2 Replies View RelatedSoftware :: Reading/Writing To Serial Ports (Rs-232)?
Dec 5, 2008I 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.
View 9 Replies View RelatedSlackware :: Reading And Writing Emails From The Console?
Apr 3, 2010I 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.
View 10 Replies View RelatedServer :: Shortlist Processes Which Are Writing / Reading To / From Disks?
Apr 2, 2010At 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?
View 3 Replies View RelatedUbuntu Networking :: Samba Crashing When Reading / Writing Many Small Files?
Mar 18, 2010Samba 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.
Ubuntu :: Pc Acting Slow When Reading / Writing Files From _ Onto Disk - Is That Normal?
Sep 27, 2010Whenever 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.
General :: After Writing Successfully A NAND Block Is This Reliable Ar Reading As A NOR Sector?
Apr 7, 2011Am 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?
View 1 Replies View RelatedProgramming :: Comparing String With Integer?
Sep 19, 2010If I have a variable, say xvar, which can take both string and integer value and I want to perform an operation in following 2 conditions:1. Either xvar is null2. xvar equals 2[ -z "$xvar" ] || [ $xvar -eq 2 ] && <some-code>Doesn't seem to work if xvar takes string valuesI know that since I have no restriction on xvar, I can get away with string comparison in second test too, ie[ -z "$xvar" ] || [ "$xvar" = "2" ] && <some-code>
But, 'Sams teach yourself shell script in 24 hrs' says that [ expr1 -eq expr2 ], if either is string, it assumes 0 valueIs it true
Programming :: Comparison Between Pointer And Integer
Jul 6, 2010I'm trying to write a simple program that lists a menu and then asks you for your decision, and you can answer with a number or the name. However, I don't know how to add the second options (name).
View 14 Replies View RelatedProgramming :: Concatenating An Integer To A String?
Oct 18, 2010I have a function that take char* I call this function in an array, and I need to pass the following:-i+" binomial" to be like "2 binomial" or whatever value of i value (i is an integer) it is pretty easy to be done in java, but how to concatenate an integer with a string and get char* or string to pass to a new function.If you missed me i just need to get the following :string =integer + string
View 5 Replies View RelatedProgramming :: Split File When Integer Is Found
Jun 25, 2010I have a file in which contains one line with a lot floating points.In the very first place and some times in the downstream, there are a few integers, surrounded by blank spaces.1 1.02-4 1.03-5 544 1.04-1 65 2.98-1 5.78-10 3.45-2 etc etc.I aim to split the file in more files each of them containing an integer and the following floatings until the next integer.
View 1 Replies View RelatedSoftware :: Reading And Writing SAC (Seismic Analysis Code) Data Files In Fortran Codes
Dec 2, 2008I 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
[Code]....
Programming :: In C Program The Value Of An Integer Variable Is Changing Rapidly
May 12, 2010In a c program the value of an integer variable is changing rapidly. I have to get the value of that variable at a particular instant from another program. How can i do it without using a file?
When i tried with extern variable as
I execute the both .c file from 2 terminals but got only value 0 printed for both var_a and var_b all the time .
Programming :: Java - Doesn't Hold Integer Values
Apr 27, 2011I have a java compiler and Im using a double intiger called Experience and when compiled and run the double intiger does not hold intiger values that are mathameticle. Like 1.5 - 1.4 will equal .100000000000000000009 and 5/3 will equal 1.0. and 1.5x 1.4 doesnt equal 2.1. Is there something I am doing wrong with double intigers? Is it the compilers fault? Could it be something thats wrong with my computer and the compilers I am using are not tat fault? Anyways double 1.5 + 1.4 does equal 2.9 so.
View 4 Replies View RelatedProgramming :: C Function Not Returning An Integer After Comparing It To A Char?
Jan 23, 2010I've got a strange bug that I cannot figure out how to solve. Here is the function.
Code:
int getnexttab(char input[], int index, int length)
{
[code]....