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  • Convert HTML to RTF (HTML2RTF converter)

    - by Luca Matteis
    I'm looking for a simple HTML2RTF converter that I can use on my website which is using a *nix like Operating System. I haven't found anything on the internet, and was hoping the SO community would help me. PS: I don't want to implement this from scratch, and it doesn't really matter what language it's in, as long as I can run it on a *nix like system. If you guys have already some personalized implementation, the language preferred would be PHP.

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  • Sockets and multithreading

    - by V0idExp
    Hi to all! I have an interesting (to me) problem... There are two threads, one for capturing data from std input and sending it through socket to server, and another one which receives data from blocking socket. So, when there's no reply from server, recv() call waits indefenitely, right? But instead of blocking only its calling thread, it blocks the overall process! Why this thing occurs?

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  • BUG - ProteaAudio with Lua does not work

    - by Stackfan
    Any idea why i cant use or cant build in Lua the ProTeaAudio ? 1) Exist [root@example ~]# yum install lua-devel Loaded plugins: presto, refresh-packagekit Setting up Install Process Package lua-devel-5.1.4-4.fc12.i686 already installed and latest version Nothing to do 2) get failed to build the RtAudio [sun@example proteaAudio_src_090204]$ make g++ -O2 -Wall -DHAVE_GETTIMEOFDAY -D__LINUX_ALSA__ -Irtaudio -Irtaudio/include -I../lua/src -I../archive/baseCode/include -c rtaudio/RtAudio.cpp -o rtaudio/RtAudio.o rtaudio/RtAudio.cpp:365: error: no ‘unsigned int RtApi::getStreamSampleRate()’ member function declared in class ‘RtApi’ rtaudio/RtAudio.cpp: In member function ‘virtual bool RtApiAlsa::probeDeviceOpen(unsigned int, RtApi::StreamMode, unsigned int, unsigned int, unsigned int, RtAudioFormat, unsigned int*, RtAudio::StreamOptions*)’: rtaudio/RtAudio.cpp:5835: error: ‘RTAUDIO_SCHEDULE_REALTIME’ was not declared in this scope rtaudio/RtAudio.cpp:5837: error: ‘struct RtAudio::StreamOptions’ has no member named ‘priority’ make: *** [rtaudio/RtAudio.o] Error 1 [sun@example proteaAudio_src_090204]$ Lua 5.1.4 Copyright (C) 1994-2008 Lua.org, PUC-Rio > require("proAudioRt"); stdin:1: module 'proAudioRt' not found: no field package.preload['proAudioRt'] no file './proAudioRt.lua' no file '/usr/share/lua/5.1/proAudioRt.lua' no file '/usr/share/lua/5.1/proAudioRt/init.lua' no file '/usr/lib/lua/5.1/proAudioRt.lua' no file '/usr/lib/lua/5.1/proAudioRt/init.lua' no file './proAudioRt.so' no file '/usr/lib/lua/5.1/proAudioRt.so' no file '/usr/lib/lua/5.1/loadall.so' stack traceback: [C]: in function 'require' stdin:1: in main chunk [C]: ?

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  • ios::nocreate error while compiling a C++ code

    - by Mohit Nanda
    While, compiling a package, written in C++ on RHEL 5.0. I am getting the following error. error: nocreate is not a member of std::ios The source-code corresponds to: ifstream tempStr(argv[4],ios::in|ios::nocreate); I have tried #g++ -O -Wno-deprecated <file.cpp> -o <file> as well as: #g++ -O -o <file> Please suggest a solution.

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  • waiting for 2 different events in a single thread

    - by João Portela
    component A (in C++) - is blocked waiting for alarm signals (not relevant) and IO signals (1 udp socket). has one handler for each of these. component B (java) - has to receive the same information the component A udp socket receives. periodicaly gives instructions that should be sent through component A udp socket. How to join both components? it is strongly desirable that: the changes to attach component B to component A are minimal (its not my code and it is not very pleasent to mess with). the time taken by the new operations (usually communicating with component B) interfere very little with the usual processing time of component A - this means that if the operations are going to take a "some" time I would rather use a thread or something to do them. note: since component A receives udp packets more frequently that it has component B instructions to forward, if necessary, it can only forward the instructions (when available) from the IO handler. my initial ideia was to develop a component C (in C++) that would sit inside the component A code (is this called an adapter?) that when instanciated starts the java process and makes the necessary connections (that not so little overhead in the initialization is not a problem). It would have 2 stacks, one for the data to give component B (lets call it Bstack) and for the data to give component A (lets call it Astack). It would sit on its thread (lets call it new-thread) waiting for data to be available in Bstack to send it over udp, and listen on the udp socket to put data on the Astack. This means that the changes to component A are only: when it receives a new UDP packet put it on the Bstack, and if there is something on the Astack sent it over its UDP socket (I decided for this because this socket would only be used in the main thread). One of the problems is that I don't know how to wait for both of these events at the same time using only one thread. so my questions are: Do I really need to use the main thread to send the data over component A socket or can I do it from the new-thread? (I think the answer is no, but I'm not sure about race conditions on sockets) how to I wait for both events? boost::condition_variable or something similar seems the solution in the case of the stack and boost::asio::io_service io_service.run() seems like the thing to use for the socket. Is there any other alternative solution for this problem that I'm not aware of? Thanks for reading this long text but I really wanted you to understand the problem.

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  • Android strace in Real device

    - by Martin Solac
    I have the following situation, I want to monitor the system calls on Android phones so I made an script to do that. With Android Emulator works perfectly (writes the traces of the application in a specific file on my Ubuntu). The problem is when I attach a real phone to analyze it, it says the following in the result file: ptrace attach failed: Operation not permitted I'm using this code to get it, but I don't understand why it works on the emulator and not in the rooted real device. This is the comand I use in perl: system("$dirTools/adb -s $Device shell strace -p $PID[1]>$dirRecordDataSet/$Date/$appName &"); Any suggestion? Thanks in advance

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  • ldd output showing shared object file whose function is not called

    - by iamrohitbanga
    I ran ldd command on an executable created by Open MPI. It shows a reference to libpthread.so Using LD_PRELOAD variable I created my own implementation of pthread_create, but from the it output it seems that MPI implementation is not calling pthread_create as I had expected. Why does ldd show pthread so file in output if it is not being used? does Open MPI not use a separate MPI thread for every node to implement the functionality?

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  • How communicate with pty via minicom or screen?

    - by gscott2112
    I am trying to provide an AT/Modem-like interface around some hardware. Follwing this post I have the server setting up a pty using openpty(). Now I can communicate with the server as expected with a client app that open the slave and communicates via read() and write() calls. However I would also like to be able to use either the screen command or minicom to issue commands by hand to the slave. However the server never seems to receive any data when trying to do this. Is there something significant I am missing with this approach?

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  • Microbenchmark showing process-switching faster than thread-switching; what's wrong?

    - by Yang
    I have two simple microbenchmarks trying to measure thread- and process-switching overheads, but the process-switching overhead. The code is living here, and r1667 is pasted below: https://assorted.svn.sourceforge.net/svnroot/assorted/sandbox/trunk/src/c/process_switch_bench.c // on zs, ~2.1-2.4us/switch #include <stdlib.h> #include <fcntl.h> #include <stdint.h> #include <stdio.h> #include <semaphore.h> #include <unistd.h> #include <sys/wait.h> #include <sys/types.h> #include <sys/time.h> #include <pthread.h> uint32_t COUNTER; pthread_mutex_t LOCK; pthread_mutex_t START; sem_t *s0, *s1, *s2; void * threads ( void * unused ) { // Wait till we may fire away sem_wait(s2); for (;;) { pthread_mutex_lock(&LOCK); pthread_mutex_unlock(&LOCK); COUNTER++; sem_post(s0); sem_wait(s1); } return 0; } int64_t timeInMS () { struct timeval t; gettimeofday(&t, NULL); return ( (int64_t)t.tv_sec * 1000 + (int64_t)t.tv_usec / 1000 ); } int main ( int argc, char ** argv ) { int64_t start; pthread_t t1; pthread_mutex_init(&LOCK, NULL); COUNTER = 0; s0 = sem_open("/s0", O_CREAT, 0022, 0); if (s0 == 0) { perror("sem_open"); exit(1); } s1 = sem_open("/s1", O_CREAT, 0022, 0); if (s1 == 0) { perror("sem_open"); exit(1); } s2 = sem_open("/s2", O_CREAT, 0022, 0); if (s2 == 0) { perror("sem_open"); exit(1); } int x, y, z; sem_getvalue(s0, &x); sem_getvalue(s1, &y); sem_getvalue(s2, &z); printf("%d %d %d\n", x, y, z); pid_t pid = fork(); if (pid) { pthread_create(&t1, NULL, threads, NULL); pthread_detach(t1); // Get start time and fire away start = timeInMS(); sem_post(s2); sem_post(s2); // Wait for about a second sleep(1); // Stop thread pthread_mutex_lock(&LOCK); // Find out how much time has really passed. sleep won't guarantee me that // I sleep exactly one second, I might sleep longer since even after being // woken up, it can take some time before I gain back CPU time. Further // some more time might have passed before I obtained the lock! int64_t time = timeInMS() - start; // Correct the number of thread switches accordingly COUNTER = (uint32_t)(((uint64_t)COUNTER * 2 * 1000) / time); printf("Number of process switches in about one second was %u\n", COUNTER); printf("roughly %f microseconds per switch\n", 1000000.0 / COUNTER); // clean up kill(pid, 9); wait(0); sem_close(s0); sem_close(s1); sem_unlink("/s0"); sem_unlink("/s1"); sem_unlink("/s2"); } else { if (1) { sem_t *t = s0; s0 = s1; s1 = t; } threads(0); // never return } return 0; } https://assorted.svn.sourceforge.net/svnroot/assorted/sandbox/trunk/src/c/thread_switch_bench.c // From <http://stackoverflow.com/questions/304752/how-to-estimate-the-thread-context-switching-overhead> // on zs, ~4-5us/switch; tried making COUNTER updated only by one thread, but no difference #include <stdlib.h> #include <stdint.h> #include <stdio.h> #include <pthread.h> #include <unistd.h> #include <sys/time.h> uint32_t COUNTER; pthread_mutex_t LOCK; pthread_mutex_t START; pthread_cond_t CONDITION; void * threads ( void * unused ) { // Wait till we may fire away pthread_mutex_lock(&START); pthread_mutex_unlock(&START); int first=1; pthread_mutex_lock(&LOCK); // If I'm not the first thread, the other thread is already waiting on // the condition, thus Ihave to wake it up first, otherwise we'll deadlock if (COUNTER > 0) { pthread_cond_signal(&CONDITION); first=0; } for (;;) { if (first) COUNTER++; pthread_cond_wait(&CONDITION, &LOCK); // Always wake up the other thread before processing. The other // thread will not be able to do anything as long as I don't go // back to sleep first. pthread_cond_signal(&CONDITION); } pthread_mutex_unlock(&LOCK); return 0; } int64_t timeInMS () { struct timeval t; gettimeofday(&t, NULL); return ( (int64_t)t.tv_sec * 1000 + (int64_t)t.tv_usec / 1000 ); } int main ( int argc, char ** argv ) { int64_t start; pthread_t t1; pthread_t t2; pthread_mutex_init(&LOCK, NULL); pthread_mutex_init(&START, NULL); pthread_cond_init(&CONDITION, NULL); pthread_mutex_lock(&START); COUNTER = 0; pthread_create(&t1, NULL, threads, NULL); pthread_create(&t2, NULL, threads, NULL); pthread_detach(t1); pthread_detach(t2); // Get start time and fire away start = timeInMS(); pthread_mutex_unlock(&START); // Wait for about a second sleep(1); // Stop both threads pthread_mutex_lock(&LOCK); // Find out how much time has really passed. sleep won't guarantee me that // I sleep exactly one second, I might sleep longer since even after being // woken up, it can take some time before I gain back CPU time. Further // some more time might have passed before I obtained the lock! int64_t time = timeInMS() - start; // Correct the number of thread switches accordingly COUNTER = (uint32_t)(((uint64_t)COUNTER * 2 * 1000) / time); printf("Number of thread switches in about one second was %u\n", COUNTER); printf("roughly %f microseconds per switch\n", 1000000.0 / COUNTER); return 0; }

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  • objdump -S - source code listing

    - by anon
    How does objdump manage to display source code? Is there a reference to the source file in the binary? I tried running strings on the binary and couldn't find any reference to the source file listed... Thanks.

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  • Segmentation Fault?

    - by user336808
    Hello, when I run this program while inputting a number greater than 46348, I get a segmentation fault. For any values below it, the program works perfectly. I am using CodeBlocks 8.02 on Ubuntu 10.04 64-bit. The code is as follows: int main() { int number = 46348; vector<bool> sieve(number+1,false); vector<int> primes; sieve[0] = true; sieve[1] = true; for(int i = 2; i <= number; i++) { if(sieve[i]==false) { primes.push_back(i); int temp = i*i; while(temp <= number) { sieve[temp] = true; temp = temp + i; } } } for(int i = 0; i < primes.size(); i++) cout << primes[i] << " "; return 0; }

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  • writing to an ioport resulting in segfaults...

    - by Sniperchild
    I'm writing for an atmel at91sam9260 arm 9 cored single board computer [glomation gesbc9260] Using request_mem_region(0xFFFFFC00,0x100,"name"); //port range runs from fc00 to fcff that works fine and shows up in /proc/iomem then i try to write to the last bit of the port at fc20 with writel(0x1, 0xFFFFFC20); and i segfault...specifically "unable to handle kernel paging request at virtual address fffffc20. I'm of the mind that i'm not allocating the right memory space... any helpful insight would be great...

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  • selecting ppp of multiple interfaces

    - by Neeraj
    Hi everyone, I am currently having a hard time on getting the mobile broadband connection running on ubuntu 10.04(lucid lynx). I am using a USB modem and used wvdial to connect to the web It went like: Sending ATZ ... OK sending some more flags OK modem initialized connecting Local IP x.x.x.x Remote IP y.y.y.y Primary DNS z.z.z.z Secondary DNS a.a.a.a (Some more output) I tested this with invalid username to make sure it is really connected and i think it was connected as connection failed with invalid usernames. Now when I do a remote ping say 8.8.8.8 (Google DNS servers), the ping says unreachable I think this might be because the system may be using the ethernet to send packets which was indeed disconnected. So can anyone help me out with this. How can I select ppp as the interface to send packets or is there some other problem. A command line solution will be appreciated as my network manager applet doesnt works correctly. Any help is much much appreciated. -- thx

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  • PHP mail() function not delivering mail

    - by Ryan Jones
    Hi there, I have a slight problem. I am using a working script (works on my testing account - shared server) to send a mail through PHP using the mail() function. I just got a dedicated server, and I haven't been able to get the function to work. I've spent the last 10 or so hours reading various documentations on BIND (for the SPF record), dovecot, sendmail and postfix trying various things to get this to work. There is clearly something that I am missing. So we know the PHP code works fine. All the headers are fine everything. We know this as it's a direct copy from my testing account. So the problem must arise somewhere in the server config. The path to sendmail is correct, and sendmail is (apparently) working fine. I've set up the script to now deliver "Sent" or "Error" based on the boolean result from the PHP mail() function. That is: if(mail($blah,$blah,$blah,$blah,$blah)) { echo "Sent"; } else { echo "Error";} And the result ALWAYS comes up as "Sent" - however, the email never arrives. Can someone suggest things to check, as I'm completely new to this (24 hours or so!). Thanks in advance. Ryan

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  • How to install the program depending on libstdc++ library

    - by Alex Farber
    My program is written in C++, using GCC on Ubuntu 9.10 64 bit. If depends on /usr/lib64/libstdc++.so.6 which actually points to /usr/lib64/libstdc++.so.6.0.13. Now I copy this program to virgin Ubuntu 7.04 system and try to run it. It doesn't run, as expected. Then I add to the program directory the following files: libstdc++.so.6.0.13 libstdc++.so.6 (links to libstdc++.so.6.0.13) and execute command: LD_LIBRARY_PATH=. ./myprogram Now everything is OK. The question: how can I write installation script for such program? myprogram file itself should be placed to /usr/local/bin. What can I do with dependencies? For example, on destination computer, /usr/lib64/libstdc++.so.6 link points to /usr/lib64/libstdc++.so.6.0.8. What can I do with this? Note: the program is closed-source, I cannot provide source code and makefile.

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  • Ubuntu 10.04: Unable to Start RabbitMQ Server Post-Installation

    - by Garland W. Binns
    After installing RabbitMQ on Ubuntu 10.04 I receive a failure message that the service was unable to start. Any insight into the issue would be greatly appreciated! Below are contents of startup_log and startup_err. Startup_log: {error_logger,{{2012,7,7},{15,50,31}},"Protocol: ~p: register error: ~p~n",["inet_tcp",{{badmatch,{error,etimedout}},[{inet_tcp_dist,listen,1},{net_kernel,start_protos,4},{net_kernel,start_protos,3},{net_kernel,init_node,2},{net_kernel,init,1},{gen_server,init_it,6},{proc_lib,init_p_do_apply,3}]}]} {error_logger,{{2012,7,7},{15,50,31}},crash_report,[[{initial_call,{net_kernel,init,['Argument__1']}},{pid,<0.20.0},{registered_name,[]},{error_info,{exit,{error,badarg},[{gen_server,init_it,6},{proc_lib,init_p_do_apply,3}]}},{ancestors,[net_sup,kernel_sup,<0.9.0]},{messages,[]},{links,[#Port<0.100,<0.17.0]},{dictionary,[{longnames,false}]},{trap_exit,true},{status,running},{heap_size,987},{stack_size,24},{reductions,512}],[]]} {error_logger,{{2012,7,7},{15,50,31}},supervisor_report,[{supervisor,{local,net_sup}},{errorContext,start_error},{reason,{'EXIT',nodistribution}},{offender,[{pid,undefined},{name,net_kernel},{mfa,{net_kernel,start_link,[[rabbitmqprelaunch877,shortnames]]}},{restart_type,permanent},{shutdown,2000},{child_type,worker}]}]} {error_logger,{{2012,7,7},{15,50,31}},supervisor_report,[{supervisor,{local,kernel_sup}},{errorContext,start_error},{reason,shutdown},{offender,[{pid,undefined},{name,net_sup},{mfa,{erl_distribution,start_link,[]}},{restart_type,permanent},{shutdown,infinity},{child_type,supervisor}]}]} {error_logger,{{2012,7,7},{15,50,31}},std_info,[{application,kernel},{exited,{shutdown,{kernel,start,[normal,[]]}}},{type,permanent}]} {"Kernel pid terminated",application_controller,"{application_start_failure,kernel,{shutdown,{kernel,start,[normal,[]]}}}"} Startup_err: Crash dump was written to: erl_crash.dump Kernel pid terminated (application_controller) ({application_start_failure,kernel,{shutdown,{kernel,start,[normal,[]]}}})

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  • How can I get `find` to ignore .svn directories?

    - by John Kugelman
    I often use the find command to search through source code, delete files, whatever. Annoyingly, because Subversion stores duplicates of each file in its .svn/text-base/ directories my simple searches end up getting lots of duplicate results. For example, I want to recursively search for uint in multiple messages.h and messages.cpp files: # find -name 'messages.*' -exec grep -Iw uint {} + ./messages.cpp: Log::verbose << "Discarding out of date message: id " << uint(olderMessage.id) ./messages.cpp: Log::verbose << "Added to send queue: " << *message << ": id " << uint(preparedMessage->id) ./messages.cpp: Log::error << "Received message with invalid SHA-1 hash: id " << uint(incomingMessage.id) ./messages.cpp: Log::verbose << "Received " << *message << ": id " << uint(incomingMessage.id) ./messages.cpp: Log::verbose << "Sent message: id " << uint(preparedMessage->id) ./messages.cpp: Log::verbose << "Discarding unsent message: id " << uint(preparedMessage->id) ./messages.cpp: for (uint i = 0; i < 10 && !_stopThreads; ++i) { ./.svn/text-base/messages.cpp.svn-base: Log::verbose << "Discarding out of date message: id " << uint(olderMessage.id) ./.svn/text-base/messages.cpp.svn-base: Log::verbose << "Added to send queue: " << *message << ": id " << uint(preparedMessage->id) ./.svn/text-base/messages.cpp.svn-base: Log::error << "Received message with invalid SHA-1 hash: id " << uint(incomingMessage.id) ./.svn/text-base/messages.cpp.svn-base: Log::verbose << "Received " << *message << ": id " << uint(incomingMessage.id) ./.svn/text-base/messages.cpp.svn-base: Log::verbose << "Sent message: id " << uint(preparedMessage->id) ./.svn/text-base/messages.cpp.svn-base: Log::verbose << "Discarding unsent message: id " << uint(preparedMessage->id) ./.svn/text-base/messages.cpp.svn-base: for (uint i = 0; i < 10 && !_stopThreads; ++i) { ./virus/messages.cpp:void VsMessageProcessor::_progress(const string &fileName, uint scanCount) ./virus/messages.cpp:ProgressMessage::ProgressMessage(const string &fileName, uint scanCount) ./virus/messages.h: void _progress(const std::string &fileName, uint scanCount); ./virus/messages.h: ProgressMessage(const std::string &fileName, uint scanCount); ./virus/messages.h: uint _scanCount; ./virus/.svn/text-base/messages.cpp.svn-base:void VsMessageProcessor::_progress(const string &fileName, uint scanCount) ./virus/.svn/text-base/messages.cpp.svn-base:ProgressMessage::ProgressMessage(const string &fileName, uint scanCount) ./virus/.svn/text-base/messages.h.svn-base: void _progress(const std::string &fileName, uint scanCount); ./virus/.svn/text-base/messages.h.svn-base: ProgressMessage(const std::string &fileName, uint scanCount); ./virus/.svn/text-base/messages.h.svn-base: uint _scanCount; How can I tell find to ignore the .svn directories?

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  • Unmanaged Process in Mono

    - by Residuum
    I want to start a quite expensive process (jackd) from a Mono application, and do not need full access to the process from the application itself. As the process is so expensive in terms of CPU usage, a Glib.IdleHandler for polling the process will not work, as it is never executed, and the GUI becomes unresponsive. Is there any way to have the cake and eating it at the same time in Mono? EDIT: I only need to be able to start and stop the process from Mono, I do not need information about the state of the process or if it has exited, as my application will register itself as a client to jackd, basically I need a "replacement" for bash's jackd &>/dev/null 2>&1 & for the System.Diagnostics.Process ;). Here is what I have so far for starting and stopping the process: public void StartJackd() { _jackd = new Process (); _jackd.StartInfo = _jackdStartup; if (_jackd.Start ()) { _jackd.EnableRaisingEvents = true; _jackd.Exited += JackdExited; } } public void StopJackd() { if (_jackd != null && !_jackd.HasExited) { _jackd.CloseMainWindow (); } } And somewhere else I have this code for registering the IdleHandler: GLib.Idle.Add(new GLib.IdleHandler(UpdateJackdConnections)); This handler will fire all the time, while the process is not running, but never, when jackd is running.

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  • debugfs_create_file doesn't create file

    - by bala1486
    Hello, I am trying to create a debugfs file using the debugfs_create_file(...). I have written a sample code for this. static int __init mmapexample_module_init(void) { file1 = debugfs_create_file("mmap_example", 0644, NULL, NULL, &my_fops)\ ; printk(KERN_ALERT "Hello, World\n"); if(file1==NULL) { printk(KERN_ALERT "Error occured\n"); } if(file1==-ENODEV) { printk(KERN_ALERT "ENODEV occured\n"); } return 0; } When i ran insmod i could get the Hello, World message but no the error message. So i think the debugfs_create_file worked fine. However i couldn't find any file in /sys/kernel/debug. The folder is there but it is empty. Can anyone help me with this? Thank you... Thanks, Bala

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  • Tee a Pipe Asynchronously

    - by User1
    I would like to write the same information to two pipes, but I don't want to wait for the first pipe to read. Here's an example mkfifo one mkfifo two echo hi | tee one two & cat one & cat two & cat one does not start reading until cat two is run. Is there a way to make cat one run without waiting?

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  • Use the output of a command as input of the next command

    - by r2b2
    so i call this php script from the command line : /usr/bin/php /var/www/bims/index.php "projects/output" and it's output is : file1 file2 file3 What I would like to do is get this output and feed to the "rm" command but i think im not doing it right : /usr/bin/php /var/www/bims/index.php "projects/output" | rm My goal is to delete whatever file names the php script outputs. What should be the proper way to do this? Thanks!

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  • Jumping into argv?

    - by jth
    Hi, I`am experimenting with shellcode and stumbled upon the nop-slide technique. I wrote a little tool that takes buffer-size as a parameter and constructs a buffer like this: [ NOP | SC | RET ], with NOP taking half of the buffer, followed by the shellcode and the rest filled with the (guessed) return address. Its very similar to the tool aleph1 described in his famous paper. My vulnerable test-app is the same as in his paper: int main(int argc, char **argv) { char little_array[512]; if(argc>1) strcpy(little_array,argv[1]); return 0; } I tested it and well, it works: jth@insecure:~/no_nx_no_aslr$ ./victim $(./exploit 604 0) $ exit But honestly, I have no idea why. Okay, the saved eip was overwritten as intended, but instead of jumping somewhere into the buffer, it jumped into argv, I think. gdb showed up the following addresses before strcpy() was called: (gdb) i f Stack level 0, frame at 0xbffff1f0: eip = 0x80483ed in main (victim.c:7); saved eip 0x154b56 source language c. Arglist at 0xbffff1e8, args: argc=2, argv=0xbffff294 Locals at 0xbffff1e8, Previous frame's sp is 0xbffff1f0 Saved registers: ebp at 0xbffff1e8, eip at 0xbffff1ec Address of little_array: (gdb) print &little_array[0] $1 = 0xbfffefe8 "\020" After strcpy(): (gdb) i f Stack level 0, frame at 0xbffff1f0: eip = 0x804840d in main (victim.c:10); saved eip 0xbffff458 source language c. Arglist at 0xbffff1e8, args: argc=-1073744808, argv=0xbffff458 Locals at 0xbffff1e8, Previous frame's sp is 0xbffff1f0 Saved registers: ebp at 0xbffff1e8, eip at 0xbffff1ec So, what happened here? I used a 604 byte buffer to overflow little_array, so he certainly overwrote saved ebp, saved eip and argc and also argv with the guessed address 0xbffff458. Then, after returning, EIP pointed at 0xbffff458. But little_buffer resides at 0xbfffefe8, that`s a difference of 1136 byte, so he certainly isn't executing little_array. I followed execution with the stepi command and well, at 0xbffff458 and onwards, he executes NOPs and reaches the shellcode. I'am not quite sure why this is happening. First of all, am I correct that he executes my shellcode in argv, not little_array? And where does the loader(?) place argv onto the stack? I thought it follows immediately after argc, but between argc and 0xbffff458, there is a gap of 620 bytes. How is it possible that he successfully "lands" in the NOP-Pad at Address 0xbffff458, which is way above the saved eip at 0xbffff1ec? Can someone clarify this? I have actually no idea why this is working. My test-machine is an Ubuntu 9.10 32-Bit Machine without ASLR. victim has an executable stack, set with execstack -s. Thanks in advance.

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