Hi,

I'm pretty new to the C++ and XS embedding and I'm not sure if this the correct section to place my question.

I've created a XS module that includes precompiled libraries and functions. One of these included C++ functions creates a shared memory segment in order to communicate with another process. Using apache's mod_cgi and simple perl scripts it works. But using mod_perl does not work.

How can I find out where the problem is? Does mod_perl deny access to the shared memory? Does anybody have a clue or an advice where I can start investigating? One possible issue could be, that the main apache process is started as root and all child processes are run as www-data. But the shared memory segment (shown by ipcs) is owned by www-data so it should be ok.

I have no possibility to debug the libs or anything like that.

Kind regards, Olli

Ubuntu 10.04.1 LTS
perl v5.10.1
libapache2-mod-perl2  2.0.4-6ubuntu1

Server version: Apache/2.2.14 (Ubuntu)
Server built:   Apr 13 2010 19:29:28
Server's Module Magic Number: 20051115:23
Server loaded:  APR 1.3.8, APR-Util 1.3.9
Compiled using: APR 1.3.8, APR-Util 1.3.9
Architecture:   32-bit
Server MPM:     Worker
  threaded:     yes (fixed thread count)
    forked:     yes (variable process count)
Server compiled with....
 -D APACHE_MPM_DIR="server/mpm/worker"
 -D APR_HAS_SENDFILE
 -D APR_HAS_MMAP
 -D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
 -D APR_USE_SYSVSEM_SERIALIZE
 -D APR_USE_PTHREAD_SERIALIZE
 -D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
 -D APR_HAS_OTHER_CHILD
 -D AP_HAVE_RELIABLE_PIPED_LOGS
 -D DYNAMIC_MODULE_LIMIT=128
 -D HTTPD_ROOT=""
 -D SUEXEC_BIN="/usr/lib/apache2/suexec"
 -D DEFAULT_PIDLOG="/var/run/apache2.pid"
 -D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
 -D DEFAULT_ERRORLOG="logs/error_log"
 -D AP_TYPES_CONFIG_FILE="/etc/apache2/mime.types"
 -D SERVER_CONFIG_FILE="/etc/apache2/apache2.conf"

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In reply to Apache, mod_perl, C++, XS and Shared Memory by oseeliger

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