Search Results

Search found 26947 results on 1078 pages for 'util linux'.

Page 512/1078 | < Previous Page | 508 509 510 511 512 513 514 515 516 517 518 519  | Next Page >

  • how can exec change the behavior of exec'ed program

    - by R Samuel Klatchko
    I am trying to track down a very odd crash. What is so odd about it is a workaround that someone discovered and which I cannot explain. The workaround is this small program which I'll refer to as 'runner': #include <stdio.h> #include <unistd.h> #include <string.h> #include <errno.h> int main(int argc, char *argv[]) { if (argc == 1) { fprintf(stderr, "Usage: %s prog [args ...]\n", argv[0]); return 1; } execvp(argv[1], argv + 1); fprintf(stderr, "execv failed: %s\n", strerror(errno)); // If exec returns because the program is not found or we // don't have the appropriate permission return 255; } As you can see, all this program does is use execvp to replace itself with a different program. The program crashes when it is directly invoked from the command line: /path/to/prog args # this crashes but works fine when it is indirectly invoked via my runner shim: /path/to/runner /path/to/prog args # works successfully For the life of me, I can figure out how having an extra exec can change the behavior of the program being run (as you can see the program does not change the environment). Some background on the crash. The crash itself is happening in the C++ runtime. Specifically, when the program does a throw, the crashing version incorrectly thinks there is no matching catch (although there is) and calls terminate. When I invoke the program via runner, the exception is properly caught. My question is any idea why the extra exec changes the behavior of the exec'ed program?

    Read the article

  • how do i claim a low-numbered port as non-root the "right way"

    - by qbxk
    I have a script that I want to run as a daemon listening on a low-numbered port (< 1024) Script is in python, though answers in perl are also acceptable. The script is being daemonized using start-stop-daemon in a startup script, which may complicate the answer What I really (think) don't want is to type ps -few and see this process running with a "root" on it's line. How do I do it? ( from my less-than-fully-educated-about-system-calls perspective, I can see 3 avenues, Run the script as root (no --user/--group/--chuid to start-stop-daemon), and have it de-escalate it's user after it claims the port Setuid root on the script (chmod u+s), and run the script as the running user, (via --user/--group/--chuid to start-stop-daemon, the startup script still has to be called as root), in the script, acquire root privileges, claim the port, and then revert back to normal user something else i'm unaware of )

    Read the article

  • bash command history update before execution of command

    - by Jon
    Hi, Bash's command history is great, especially it is useful when adding the history -a command to the COMMAND_PROMPT. However, I'm wondering if there is a way to log the commands to a file as soon as the Return key is pressed, e.g. before starting the command and not on completion of the command (using the COMMAND_PROMPT option would save the command once the prompt is there again). I read about auditing programs like snoopy and session recorder like script but I thought they're already too complex for the simple question I have. I guess that deactivating that script logs all the output of the command would lead already in the right direction but isn't there a quicker way to solve that probelm? Thanks, Jon

    Read the article

  • Perl: Recursively rename all files and directories

    - by user305801
    I need to recursively rename every file and directory. I convert spaces to underscores and make all file/directory names to lowercase. How can I make the following script rename all files in one run? Currently the script needs to be run several times before all the files/directories are converted. The code is below: #!/usr/bin/perl use File::Find; $input_file_dir = $ARGV[0]; sub process_file { $clean_name=lc($_); $clean_name=~s/\s/_/g; rename($_,$clean_name); print "file/dir name: $clean_name\n"; } find(\&process_file, $input_file_dir);

    Read the article

  • Untar, ungz, gz, tar - how do you remember all the useful options?

    - by deadprogrammer
    I am pretty sure I am not the only one with the following problem: every time I need to uncompress a file in *nix I can't remember all the switches, and end up googling it, which is surprizing considering how often I need to do this. Do you have a good compression cheat sheet? Or how about a mnemonic for all those nasty switches in tar? I am making this article a wiki so that we can create a nice cheat sheet here. Oh, and about man pages: is there's one thing they are not helpful for, it's for figuring out how to uncompress a file.

    Read the article

  • Bash script to replace spaces in file names

    - by armandino
    Can anyone recommend a safe solution to recursively replace spaces with underscores in file and directory names starting from a given root directory? For example, $ tree . |-- a dir | `-- file with spaces.txt `-- b dir |-- another file with spaces.txt `-- yet another file with spaces.pdf becomes $ tree . |-- a_dir | `-- file_with_spaces.txt `-- b_dir |-- another_file_with_spaces.txt `-- yet_another_file_with_spaces.pdf

    Read the article

  • not able to register sip user on red5server, using red5phone

    - by sunil221
    I start the red5, and then i start red5phone i try to register sip user , details i provide are username = 999999 password = **** ip = asteriskserverip and i got --- Registering contact -- sip:[email protected]:5072 the right contact could be --- sip :99999@asteriskserverip this is the log: SipUserAgent - listen -> Init... Red5SIP register [SIPUser] register RegisterAgent: Registering contact <sip:[email protected]:5072> (it expires in 3600 secs) RegisterAgent: Registration failure: No response from server. [SIPUser] SIP Registration failure Timeout RegisterAgent: Failed Registration stop try. Red5SIP Client leaving app 1 Red5SIP Client closing client 35C1B495-E084-1651-0C40-559437CAC7E1 Release ports: sip port 5072 audio port 3002 Release port number:5072 Release port number:3002 [SIPUser] close1 [SIPUser] hangup [SIPUser] closeStreams RTMPUser stopStream [SIPUser] unregister RegisterAgent: Unregistering contact <sip:[email protected]:5072> SipUserAgent - hangup -> Init... SipUserAgent - closeMediaApplication -> Init... [SIPUser] provider.halt RegisterAgent: Registration failure: No response from server. [SIPUser] SIP Registration failure Timeout please let me know if i am doing anything wrong. regards Sunil

    Read the article

  • how to get ip address of my computer

    - by asthagoyal
    hello i want to get ipaddress of my computer in variable ip thru this code but it assign nothing in ip char comm[100]; int s=0; char ip[100]; sprintf(comm,"export ip=`/sbin/ifconfig eth0 | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}'`"); s=system(comm); printf("\n ip is %s",ip);

    Read the article

  • Too many open files in one of my java routine.

    - by Irfan Zulfiqar
    I have a multithreaded code that has to generated a set of objects and write them to a file. When I run it I sometime get "Too many open files" message in Exception. I have checked the code to make sure that all the file streams are being closed properly. Here is the stack trace. When I do ulimit -a, open files allowed is set to 1024. We think increasing this number is not a viable option / solution. [java] java.io.FileNotFoundException: /export/event_1_0.dtd (Too many open files) [java] at java.io.FileInputStream.open(Native Method) [java] at java.io.FileInputStream.<init>(FileInputStream.java:106) [java] at java.io.FileInputStream.<init>(FileInputStream.java:66) [java] at sun.net.www.protocol.file.FileURLConnection.connect(FileURLConnection.java:70) [java] at sun.net.www.protocol.file.FileURLConnection.getInputStream(FileURLConnection.java:161) [java] at java.net.URL.openStream(URL.java:1010) Now what we have identified so far by looking closely at the list of open files is that the VM is opening same class file multiple times. /export/BaseEvent.class 236 /export/EventType1BaseEvent.class 60 /export/EventType2BaseEvent.class 48 /export/EventType2.class 30 /export/EventType1.class 14 Where BaseEvent is partent of all the classes and EventType1 ant EventType2 inherits EventType1BaseEvent and EventType2BaseEvent respectively. Why would a class loader load the same class file 200+ times. It seems it is opening up the base class as many time it create any child instance. Is this normal? Can it be handler any other way apart from increasing the number of open files?

    Read the article

  • Why is scp not overwriting my destination file?

    - by Noli
    I'm trying to back up a file via the command scp /tmp/backup.tar.gz hostname:/home/user/backup.tar.gz When I run it, the scp progress bar shows up and it looks like its transferring the file, however when I log into the destination server to check the file, the timestamp and filesize haven't changed from the older version, so it looks like scp didn't overwrite the old file at all. It only sees to work when I manually delete the file from the destination server. I'm running ubuntu, and this is happening on two servers: one cygwin ssh, and one fedora core 3. Anyone have any idea why this is happening? I thought scp would ONLY overwrite existing files.. Thanks

    Read the article

  • How can I get a list of licenses from intalled RPMs?

    - by Peter
    We've been asked to list all the software and licenses used in our organization. Without deciding the value of this request, I'd like to get my Fedora laptop to answer the question easily. rpm -qa Gives me a list of packages, but no license data. My next step is to take that output and write a script to query each package's license. Anyone got an easier idea?

    Read the article

  • Shell - Run additional command on failure

    - by Shawn
    I have this script that I am currently running that works great for all instances but one: #!/bin/sh pdfopt test.pdf test.opt.pdf &>/dev/null pdf2swf test.opt.pdf test.swf [ "$?" -ne 0 ] && exit 2 More lines to execute follow the above code ... How would I go about changing this script to run "pdf2swf test.pdf test.swf" if "pdf2swf test.opt.pdf test.swf" fails? If the second attempt fails, then I would "exit 2". Thanks

    Read the article

  • How to completely wipe rubygems along with rails etc

    - by Earlz
    Ok, so I decided I'd be cool and try to use Rails3 that's in beta. Then, things were getting hard to manage so I got rvm. I installed ruby 1.9.2-head in rvm and things were working, and then a computer restart later rails wouldn't start up. So I figured I'd just try running the system ruby and start rails in it. same error. Then, I uninstalled rails3 and got rails: no such file or directory type errors.. So now I'm royally screwed because rails2 is still installed but will not uninstall because of invisible dependencies, along with a lot of other random gems. How do I completely clear out all ruby gems and such so I can start anew?

    Read the article

  • cmake source and out-of-source navigation

    - by idimba
    Hi, cmake advises to use out-of-source builds. While in general I like the idea I find it not comfortable to navigate from out-of-source sub directory to the corresponding source directory. I frequently need the code to perform some actions with code (e.g. grep, svn command etc.). Is there an easy way in shell to navigate from out-of-source sub directory to the corresponding source directory? Thanks Dima

    Read the article

  • HOW-TO Make computer sing

    - by Ofir
    Hi, I'm trying to develop an online application where the user writes some text and the software sings it back to the user. I can currently generate the audio file with the words spoken by the computer using espeak, but I have no idea how to make it sound like a song, how to add rhythm to it. I'm able to change the pitch and tempo using rubberband, but that's as far as I've gotten. Does anyone have a clue how to make this happen?

    Read the article

  • segfault on vector<struct>

    - by Andre
    Hello, I created a struct to hold some data and then declared a vector to hold that struct. But when I do a push_back I get damn segfault and I have no idea why! My struct is defines as: typedef struct Group { int codigo; string name; int deleted; int printers; int subpage; /*included this when it started segfaulting*/ Group(){ name.reserve(MAX_PRODUCT_LONG_NAME); } ~Group(){ name.clear(); } Group(const Group &b) { codigo = b.codigo; name = b.name; deleted = b.deleted; printers = b.printers; subpage = b.subpage; } /*end of new stuff*/ }; Originally, the struct didn't have the copy, constructor or destructor. I added them latter when I read this post below. http://stackoverflow.com/questions/676575/seg-fault-after-is-item-pushed-onto-stl-container but the end result is the same. There is one this that is bothering me as hell! When I first push some data into the vector, everything goes fine. Later on in the code when I try to push some more data into the vector, my app just segfaults! The vector is declared vector<Group> Groups and is a global variable to the file where I am using it. No externs anywhere else, etc... I can trace the error to: _M_deallocate(this->_M_impl._M_start, this->_M_impl._M_end_of_storage- this->_M_impl._M_start); in vector.tcc when I finish adding/copying the last element to the vector.... As far as I can tell. I shouldn't be needing anything to do with a copy constructor as a shallow copy should be enough for this. I'm not even allocating any space (but I did a reserve for the string to try out). I have no idea what the problem is! I'm running this code on OpenSuse 10.2 with gcc 4.1.2 I'm not really to eager to upgrade gcc because of backward compatibility issues... This code worked "perfectly" on my windows machine. I compiled it with gcc 3.4.5 mingw without any problems... help! --- ... --- :::EDIT::: I push data Group tmp_grp; (...) tmp_grp.name = "Nova "; tmp_grp.codigo=GetGroupnextcode(); tmp_grp.deleted=0; tmp_grp.printers=0; tmp_grp.subpage=0; Groups.push_back(tmp_grp);

    Read the article

  • SED: Matching on 2 patterns on the same line

    - by Brian Knott
    Hi I want to delete a line using sed if it matches 2 regular expressions in the same line. EG the line starts with /* and end with */ (comment). The following script will do most of that. sed -e '/^\/*/ d' -e '/*\/$/ d' filename This script will remove all lines that start with * and end with */. I want it to remove the line only if is meets both criteria not one.

    Read the article

  • Looping an executable to get the result from Python script

    - by fx
    In my python script, I need to call within a for loop an executable, and waiting for that executable to write the result on the "output.xml". How do I manage to use wait() & how do I know when one of my executable is finished generating the result to get the result? How do I close that process and open a new one to call again the executable and wait for the new result? import subprocess args = ("bin/bar") popen = subprocess.Popen(args) I need to wait for the output from "bin/bar" to generate the "output.xml" and from there, read it's content. for index, result in enumerate(results): myModule.callSubProcess(index) #this is where the problem is. fileOutput = open("output.xml") parseAndStoreInSQLiteFileOutput(index, file)

    Read the article

  • Other users on my Server?

    - by Jennifer Weinberg
    I'm buying a Server from a person (that I don't know really well) and I want to make sure that the previous owner hasn't got any access anymore. It's an Ubuntu Virtual Server and I already received the admin access (via shell). How can I find out if there are still other accounts left, who are still able to access my server (e.g. with a still existing shell account, ftp or another type of user account)? And how can I delete them if these accounts exist? Best regards, Jennifer

    Read the article

  • Valgrind 'noise', what does it mean?

    - by Chris Huang-Leaver
    When I used valgrind to help debug an app I was working on I notice a huge about of noise which seems to be complaining about standard libraries. As a test I did this; echo 'int main() {return 0;}' | gcc -x c -o test - Then I did this; valgrind ./test ==1096== Use of uninitialised value of size 8 ==1096== at 0x400A202: _dl_new_object (in /lib64/ld-2.10.1.so) ==1096== by 0x400607F: _dl_map_object_from_fd (in /lib64/ld-2.10.1.so) ==1096== by 0x4007A2C: _dl_map_object (in /lib64/ld-2.10.1.so) ==1096== by 0x400199A: map_doit (in /lib64/ld-2.10.1.so) ==1096== by 0x400D495: _dl_catch_error (in /lib64/ld-2.10.1.so) ==1096== by 0x400189E: do_preload (in /lib64/ld-2.10.1.so) ==1096== by 0x4003CCD: dl_main (in /lib64/ld-2.10.1.so) ==1096== by 0x401404B: _dl_sysdep_start (in /lib64/ld-2.10.1.so) ==1096== by 0x4001471: _dl_start (in /lib64/ld-2.10.1.so) ==1096== by 0x4000BA7: (within /lib64/ld-2.10.1.so) * large block of similar snipped * ==1096== Use of uninitialised value of size 8 ==1096== at 0x4F35FDD: (within /lib64/libc-2.10.1.so) ==1096== by 0x4F35B11: (within /lib64/libc-2.10.1.so) ==1096== by 0x4A1E61C: _vgnU_freeres (vg_preloaded.c:60) ==1096== by 0x4E5F2E4: __run_exit_handlers (in /lib64/libc-2.10.1.so) ==1096== by 0x4E5F354: exit (in /lib64/libc-2.10.1.so) ==1096== by 0x4E48A2C: (below main) (in /lib64/libc-2.10.1.so) ==1096== ==1096== ERROR SUMMARY: 3819 errors from 298 contexts (suppressed: 876 from 4) ==1096== malloc/free: in use at exit: 0 bytes in 0 blocks. ==1096== malloc/free: 0 allocs, 0 frees, 0 bytes allocated. ==1096== For counts of detected errors, rerun with: -v ==1096== Use --track-origins=yes to see where uninitialised values come from ==1096== All heap blocks were freed -- no leaks are possible. You can see the full result here: http://pastebin.com/gcTN8xGp I have two questions; firstly is there a way to suppress all the noise? --show-below-main is set to no by default, but there doesn't appear to be a --show-after-main equivalent.

    Read the article

  • pthread and recursively calling execvp in C

    - by eduke
    To begin I'm sorry for my english :) I looking for a way to create a thread each time my program finds a directory, in order to call the program itself but with a new argv[2] argument (which is the current dir). I did it successfully with fork() but with pthread I've some difficulties. I don't know if I can do something like that : #include <unistd.h> #include <stdlib.h> #include <stdio.h> #include <string.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/wait.h> #include <dirent.h> int main(int argc, char **argv) { pthread_t threadID[10] = {0}; DIR * dir; struct dirent * entry; struct stat status; pthread_attr_t attr; pthread_attr_init(&attr); int i = 0; char *res; char *tmp; char *file; if(argc != 3) { printf("Usage : %s <file> <dir>\n", argv[0]); exit(EXIT_FAILURE); } if(stat(argv[2],&status) == 0) { dir = opendir(argv[2]); file = argv[1]; } else exit(EXIT_FAILURE); while ((entry = readdir(dir))) { if (strcmp(entry->d_name, ".") && strcmp(entry->d_name, "..")) { tmp = malloc(strlen(argv[2]) + strlen(entry->d_name) + 2); strcpy(tmp, argv[2]); strcat(tmp, "/"); strcat(tmp, entry->d_name); stat(tmp, &status); if (S_ISDIR(status.st_mode)) { argv[2] = tmp; pthread_create( &threadID[i], &attr, execvp(argv[0], argv), NULL); printf("New thread created : %d", i); i++; } else if (!strcmp(entry->d_name, file)) { printf(" %s was found - Thread number = %d\n",tmp, i); break; } free(tmp); } } pthread_join( threadID[i] , &res ); exit(EXIT_SUCCESS); } Actually it doesn't works : pthread_create( &threadID[i], &attr, execvp(argv[0], argv), NULL); I have no runtime error, but when the file to find is in another directory, the thread is not created and so execvp(argv[0], argv) is not called... Thank you for you help, Simon

    Read the article

  • How can I prevent default_environment variables from getting set by Capistrano's sudo action?

    - by Logan Koester
    My deploy.rb sets some environment variables to use the regular user's local Ruby rather than the system-wide one. set :default_environment, { :PATH => '/home/myapp/.rvm/bin:/home/myapp/.rvm/bin:/home/myapp/.rvm/rubies/ruby-1.9.1-p378/bin:/home/myapp/.rvm/gems/ruby-1.9.1-p378/bin:/home/myapp/.rvm/gems/ruby-1.9.1-p378%global/bin:/home/myapp/bin:/usr/bin:/opt/local/bin:/opt/local/sbin:/usr/local/bin:/usr/local/sbin:/usr/sbin:/sbin:/bin:/usr/games', :RUBY_VERSION => 'ruby-1.9.1-p378', :GEM_HOME => '/home/myapp/.rvm/gems/ruby-1.9.1-p378', :GEM_PATH => '/home/myapp/.rvm/gems/ruby-1.9.1-p378:/home/myapp/.rvm/gems/ruby-1.9.1-p378%global' } Naturally, when a task is using sudo, I would expect the system-wide ruby to be used instead. But it seems the environment variables are being set anyway, which is obviously invalid for the root user and returns an error: executing "sudo -p 'sudo password: ' /etc/init.d/god stop" servers: ["myapp.com"] [myapp.com] executing command command finished failed: "env PATH=/home/myapp/.rvm/bin:/home/myapp/.rvm/bin:/home/myapp/.rvm/rubies/ruby-1.9.1-p378/bin:/home/myapp/.rvm/gems/ruby-1.9.1-p378/bin:/home/myapp/.rvm/gems/ruby-1.9.1-p378%global/bin:/home/myapp/bin:/usr/bin:/opt/local/bin:/opt/local/sbin:/usr/local/bin:/usr/local/sbin:/usr/sbin:/sbin:/bin:/usr/games RUBY_VERSION=ruby-1.9.1-p378 GEM_HOME=/home/myapp/.rvm/gems/ruby-1.9.1-p378 GEM_PATH=/home/myapp/.rvm/gems/ruby-1.9.1-p378:/home/myapp/.rvm/gems/ruby-1.9.1-p378%global sh -c 'sudo -p '\\''sudo password: '\\'' /etc/init.d/god stop'" on myapp.com It makes no difference whether I use capistrano's sudo "system call" or the regular run "sudo system call". How can I avoid this?

    Read the article

< Previous Page | 508 509 510 511 512 513 514 515 516 517 518 519  | Next Page >