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  • WebSeal and jsp content updated by Ajax

    - by lior chaga
    Hey, I have a problem running an application on environment with WebSeal. It is a web application with Java server that contains many parts that are replcaed within the page according to user input. For instance - a form called Outer.jsp may contain a form:options combo-box (by spring-forms), that uppon selection of an option, a certain Div is updated with a content produced by a jsp and fetched by an Ajax call (the ajax impementation in the client is done by Prototype JavaScript framework 1.5.1.2). Let's call the content fetched by ajax - Inner.jsp So Outer.jsp is fetching Inner.jsp, which in turn uses js functions in files included by the Outer.jsp. This, I think, is where my problem starts - Inner.jsp is not familiar with any of the functions included in Outer.jsp. And so, almost any operation performed by Inner.jsp is failing miserably. Needless to say - this works perfect when running on environment without WebSeal. Note that the scripting is enabled in WebSeal junction (with the -J option). I also see that the content returned by the Ajax call includes a document.cookie added by WebSeal (not sure it matters to this problem) Can anyone assist? Thanks! Lior

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  • SQL Server 2008 cluster freezing

    - by Ed Leighton-Dick
    We have run into a strange situation in which a SQL Server 2008 single-node cluster hangs. As background, we are rebuilding a Windows Server 2003/SQL Server 2005 two-node cluster using Windows 2008 and SQL Server 2008. Here's the timeline: Evicted the passive node (server B) from the Windows 2003/SQL 2005 cluster. The active node now functions as a single-node cluster with no problems. Wiped server B's disks and installed Windows 2008 and SQL Server 2008 as a single-node cluster. Since we do not want to the two clusters to communicate yet, we left the cluster's private network "heartbeat" adapter unconfigured. The cluster comes up and functions normally. Moved all databases to the new cluster. Cluster continues to function normally. Turned off server A (old cluster) in preparation for rebuilding as the second node of the new cluster. SQL Server instance on server B (new cluster) locks up, even though it should have no knowledge of or interaction with server A. Restarted server A. SQL Server instance on server B (new cluster) immediately begins working again. Things we have tried: The new cluster's name responds to ping and NETBIOS requests, even while the SQL Server is hung. We have confirmed that no IP address is assigned to the old heartbeat adapter, and it is not pulling an IP address from DHCP. Disabling the heartbeat's network card has the same effect. No errors were generated in any logs - Windows or SQL. When the error first occurred, it sat in the hung state for quite some time (well over 10 minutes) before anyone figured out what was going on. This would seem to eliminate any sort of normal cluster timeout in which it would have been searching for the other node (even if one had been configured). Server B is running Windows 2008 SP2, fully patched, and SQL Server 2008 SP1 CU7 (10.0.2775).

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  • Selective Pointer device remapping in linux

    - by user6368
    I just got an HP 2710p (hp tablet, with digitizer), and I've played around with linux for a while now, and thought I would go ahead and install it. Everything works fine, excepting normal tablet functions, which is to be expected. I'm working on the screen rotation, and there are on-screen keyboards, etc, but I'm having issues with the stylus. I can tap and left click with the stylus as normal, but the side button (which in windows functions as a right mouse button) appears as a 'button 2' to xev (a middle/scroll wheel button). I can switch 'button 2' and 'button 3' universally using xmodmap, but I'd like to do so exclusively for stylus so I don't screw up regular pointing devices. Altering xorg.conf (which is surprisingly bare) with the recommended sections (adding sections for each of the stylus buttons) does nothing. I'm running crunchbang, which is an ubuntu/debian varient with openbox as the windows manager. Thanks Also, as a seperate note, does anybody know how to detect when I rotate and/or latch the lid shut? I was thinking maybe I could run a script to switch the buttons when I close it, but I can't find any information.

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  • sudoer scheme for another web developer that retains my future control of a virtual server?

    - by Tchalvak
    Background: Virtual Private Server I have a virtual private server that I'm looking to host multiple websites on, and provide access to another web developer. I don't care about putting too many constraints on him, though I wouldn't mind isolating the site that he'll be developing from other sites on the server that I will develop. The problem: retain control Mainly what I want is to make sure that I retain control over the server in the future. I want to reserve the ability to create/promote/demote and other administrative functions that don't deal with web software. If I make him an admin, he can sudo su - and become root and remove root control from me, for example. I need him not to be able to: take away other admin permissions change the root password have control over other security/administrative functions I would like him to still be able to: install software (through apt-get) restart apache access mysql configure mysql/apache reboot edit web development configuration type files in /etc/ Other Standard Setups would be happily considered I've never really set up a good sudoers file, so simple example setups would be very useful, even if they're only somewhat similar to the settings that I'm hoping for above. Edit: I have not yet finalized permissions, standard, useful sudo setups are certainly an option, the lists above are more what I'm hoping I can do, I don't know that that setup can be done.

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  • How flexible is the 'indirect' function?

    - by Chuck
    My curiosity pushes me to ask this question. If I were to have a series of functions that referenced a different column in a worksheet but all ended on the same row of data is there a way to point the 'row' part of a cell reference to a blank cell and use it has a variable to show the results of the functions up to a desired row simultaneously? Example: =Average('worksheet 1'.$A$1:'worksheet 1'.$A100) =Max('worksheet 1'.$B$1:'worksheet 1'.$B100) =Min('worksheet 1'.$C$1:'worksheet 1'.$C100) =Sum('worksheet 1'.$D$1:'worksheet 1'.$D100) Pseudo formulas... =Average('worksheet 1'.$A$1:'worksheet 1'.$A*('worksheet 2'.$A$1)*) =Max('worksheet 1'.$B$1:'worksheet 1'.$B*('worksheet 2'.$A$1)*) =Min('worksheet 1'.$C$1:'worksheet 1'.$C*('worksheet 2'.$A$1)*) =Sum('worksheet 1'.$D$1:'worksheet 1'.$D*('worksheet 2'.$A$1)*) Where 'worksheet 2'.$A$1 would only contain a number corresponding to a row in 'worksheet 1'. After stumbling upon and playing with the indirect() function I have only been able to replace the entire cell reference (Column and Row) with any success. The formula so far =SUM('worksheet 1'.C3:INDIRECT(A1)) Where A1 is on 'worksheet 2' and contains a full cell reference pointing to 'worksheet 1'. Any pointers?

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  • Does Guest WiFi on an Access Point make any sense?

    - by uos??
    I have a Belkin WiFi Router which offers a feature of a secondary Guest Access WiFi network. Of course, the idea is that the Guest network doesn't have access to the computers/devices on the main network. I also have a Comcast-issues Cable Modem/Router device with mutliple wired ports, but no WiFi-capabilities. I prefer to only run one router/DHCP/NAT instead of both the Comcast Router and the Belkin Router, so I can disable the Routing functions of the Belkin and allow the Comcast Router to But if I disable the Routing functions of the Belkin device, the Guest WiFi network is still available. Is this configuration just as secure as when the Belkin acts as a Router? I guess the question comes down to this: Do Guest WiFi's provide security by 1) only allowing requests to IPs found in-front of the device, or do they work by 2) disallowing requests to IPs on the same subnet? 1) Would mean that Guest WiFi on an access point provides no benefit 2) Would mean that the Guest WiFi functionality can work even if the device is just an access point. Or maybe something else entirely?

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  • puma init.d for centos 6 fails with runuser: user /var/log/puma.log does not exist

    - by Rubytastic
    Trying to get a init.d/puma to work on Centos 6. It throws error runuser: user /var/log/puma.log does not exist I run this from the /srv/books/current folder but it fails. I tried to debug the values but not quite get what is missing and why it throws this error. #! /bin/sh # puma - this script starts and stops the puma daemon # # chkconfig: - 85 15 # description: Puma # processname: puma # config: /etc/puma.conf # pidfile: /srv/books/current/tmp/pids/puma.pid # Author: Darío Javier Cravero &lt;[email protected]> # # Do NOT "set -e" # Original script https://github.com/puma/puma/blob/master/tools/jungle/puma # It was modified here by Stanislaw Pankevich <[email protected]> # to run on CentOS 5.5 boxes. # Script works perfectly on CentOS 5: script uses its native daemon(). # Puma is being stopped/restarted by sending signals, control app is not used. # Source function library. . /etc/rc.d/init.d/functions # Source networking configuration. . /etc/sysconfig/network # Check that networking is up. [ "$NETWORKING" = "no" ] && exit 0 # PATH should only include /usr/* if it runs after the mountnfs.sh script PATH=/usr/local/bin:/usr/local/sbin/:/sbin:/usr/sbin:/bin:/usr/bin DESC="Puma rack web server" NAME=puma DAEMON=$NAME SCRIPTNAME=/etc/init.d/$NAME CONFIG=/etc/puma.conf JUNGLE=`cat $CONFIG` RUNPUMA=/usr/local/bin/run-puma # Skipping the following non-CentOS string # Load the VERBOSE setting and other rcS variables # . /lib/init/vars.sh # CentOS does not have these functions natively log_daemon_msg() { echo "$@"; } log_end_msg() { [ $1 -eq 0 ] && RES=OK; logger ${RES:=FAIL}; } # Define LSB log_* functions. # Depend on lsb-base (>= 3.0-6) to ensure that this file is present. . /lib/lsb/init-functions # # Function that performs a clean up of puma.* files # cleanup() { echo "Cleaning up puma temporary files..." echo $1; PIDFILE=$1/tmp/puma/puma.pid STATEFILE=$1/tmp/puma/puma.state SOCKFILE=$1/tmp/puma/puma.sock rm -f $PIDFILE $STATEFILE $SOCKFILE } # # Function that starts the jungle # do_start() { log_daemon_msg "=> Running the jungle..." for i in $JUNGLE; do dir=`echo $i | cut -d , -f 1` user=`echo $i | cut -d , -f 2` config_file=`echo $i | cut -d , -f 3` if [ "$config_file" = "" ]; then config_file="$dir/puma/config.rb" fi log_file=`echo $i | cut -d , -f 4` if [ "$log_file" = "" ]; then log_file="$dir/puma/puma.log" fi do_start_one $dir $user $config_file $log_file done } do_start_one() { PIDFILE=$1/puma/puma.pid if [ -e $PIDFILE ]; then PID=`cat $PIDFILE` # If the puma isn't running, run it, otherwise restart it. if [ "`ps -A -o pid= | grep -c $PID`" -eq 0 ]; then do_start_one_do $1 $2 $3 $4 else do_restart_one $1 fi else do_start_one_do $1 $2 $3 $4 fi } do_start_one_do() { log_daemon_msg "--> Woke up puma $1" log_daemon_msg "user $2" log_daemon_msg "log to $4" cleanup $1; daemon --user $2 $RUNPUMA $1 $3 $4 } # # Function that stops the jungle # do_stop() { log_daemon_msg "=> Putting all the beasts to bed..." for i in $JUNGLE; do dir=`echo $i | cut -d , -f 1` do_stop_one $dir done } # # Function that stops the daemon/service # do_stop_one() { log_daemon_msg "--> Stopping $1" PIDFILE=$1/tmp/puma/puma.pid STATEFILE=$1/tmp/puma/puma.state echo $PIDFILE if [ -e $PIDFILE ]; then PID=`cat $PIDFILE` echo "Pid:" echo $PID if [ "`ps -A -o pid= | grep -c $PID`" -eq 0 ]; then log_daemon_msg "---> Puma $1 isn't running." else log_daemon_msg "---> About to kill PID `cat $PIDFILE`" # pumactl --state $STATEFILE stop # Many daemons don't delete their pidfiles when they exit. kill -9 $PID fi cleanup $1 else log_daemon_msg "---> No puma here..." fi return 0 } # # Function that restarts the jungle # do_restart() { for i in $JUNGLE; do dir=`echo $i | cut -d , -f 1` do_restart_one $dir done } # # Function that sends a SIGUSR2 to the daemon/service # do_restart_one() { PIDFILE=$1/tmp/puma/puma.pid i=`grep $1 $CONFIG` dir=`echo $i | cut -d , -f 1` if [ -e $PIDFILE ]; then log_daemon_msg "--> About to restart puma $1" # pumactl --state $dir/tmp/puma/state restart kill -s USR2 `cat $PIDFILE` # TODO Check if process exist else log_daemon_msg "--> Your puma was never playing... Let's get it out there first" user=`echo $i | cut -d , -f 2` config_file=`echo $i | cut -d , -f 3` if [ "$config_file" = "" ]; then config_file="$dir/config/puma.rb" fi log_file=`echo $i | cut -d , -f 4` if [ "$log_file" = "" ]; then log_file="$dir/log/puma.log" fi do_start_one $dir $user $config_file $log_file fi return 0 } # # Function that statuss then jungle # do_status() { for i in $JUNGLE; do dir=`echo $i | cut -d , -f 1` do_status_one $dir done } # # Function that sends a SIGUSR2 to the daemon/service # do_status_one() { PIDFILE=$1/tmp/puma/pid i=`grep $1 $CONFIG` dir=`echo $i | cut -d , -f 1` if [ -e $PIDFILE ]; then log_daemon_msg "--> About to status puma $1" pumactl --state $dir/tmp/puma/state stats # kill -s USR2 `cat $PIDFILE` # TODO Check if process exist else log_daemon_msg "--> $1 isn't there :(..." fi return 0 } do_add() { str="" # App's directory if [ -d "$1" ]; then if [ "`grep -c "^$1" $CONFIG`" -eq 0 ]; then str=$1 else echo "The app is already being managed. Remove it if you want to update its config." exit 1 fi else echo "The directory $1 doesn't exist." exit 1 fi # User to run it as if [ "`grep -c "^$2:" /etc/passwd`" -eq 0 ]; then echo "The user $2 doesn't exist." exit 1 else str="$str,$2" fi # Config file if [ "$3" != "" ]; then if [ -e $3 ]; then str="$str,$3" else echo "The config file $3 doesn't exist." exit 1 fi fi # Log file if [ "$4" != "" ]; then str="$str,$4" fi # Add it to the jungle echo $str >> $CONFIG log_daemon_msg "Added a Puma to the jungle: $str. You still have to start it though." } do_remove() { if [ "`grep -c "^$1" $CONFIG`" -eq 0 ]; then echo "There's no app $1 to remove." else # Stop it first. do_stop_one $1 # Remove it from the config. sed -i "\\:^$1:d" $CONFIG log_daemon_msg "Removed a Puma from the jungle: $1." fi } case "$1" in start) [ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME" if [ "$#" -eq 1 ]; then do_start else i=`grep $2 $CONFIG` dir=`echo $i | cut -d , -f 1` user=`echo $i | cut -d , -f 2` config_file=`echo $i | cut -d , -f 3` if [ "$config_file" = "" ]; then config_file="$dir/config/puma.rb" fi log_file=`echo $i | cut -d , -f 4` if [ "$log_file" = "" ]; then log_file="$dir/log/puma.log" fi do_start_one $dir $user $config_file $log_file fi case "$?" in 0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;; 2) [ "$VERBOSE" != no ] && log_end_msg 1 ;; esac ;; stop) [ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME" if [ "$#" -eq 1 ]; then do_stop else i=`grep $2 $CONFIG` dir=`echo $i | cut -d , -f 1` do_stop_one $dir fi case "$?" in 0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;; 2) [ "$VERBOSE" != no ] && log_end_msg 1 ;; esac ;; status) # TODO Implement. log_daemon_msg "Status $DESC" "$NAME" if [ "$#" -eq 1 ]; then do_status else i=`grep $2 $CONFIG` dir=`echo $i | cut -d , -f 1` do_status_one $dir fi case "$?" in 0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;; 2) [ "$VERBOSE" != no ] && log_end_msg 1 ;; esac ;; restart) log_daemon_msg "Restarting $DESC" "$NAME" if [ "$#" -eq 1 ]; then do_restart else i=`grep $2 $CONFIG` dir=`echo $i | cut -d , -f 1` do_restart_one $dir fi case "$?" in 0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;; 2) [ "$VERBOSE" != no ] && log_end_msg 1 ;; esac ;; add) if [ "$#" -lt 3 ]; then echo "Please, specifiy the app's directory and the user that will run it at least." echo " Usage: $SCRIPTNAME add /path/to/app user /path/to/app/config/puma.rb /path/to/app/config/log/puma.log" echo " config and log are optionals." exit 1 else do_add $2 $3 $4 $5 fi case "$?" in 0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;; 2) [ "$VERBOSE" != no ] && log_end_msg 1 ;; esac ;; remove) if [ "$#" -lt 2 ]; then echo "Please, specifiy the app's directory to remove." exit 1 else do_remove $2 fi case "$?" in 0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;; 2) [ "$VERBOSE" != no ] && log_end_msg 1 ;; esac ;; *) echo "Usage:" >&2 echo " Run the jungle: $SCRIPTNAME {start|stop|status|restart}" >&2 echo " Add a Puma: $SCRIPTNAME add /path/to/app user /path/to/app/config/puma.rb /path/to/app/config/log/puma.log" echo " config and log are optionals." echo " Remove a Puma: $SCRIPTNAME remove /path/to/app" echo " On a Puma: $SCRIPTNAME {start|stop|status|restart} PUMA-NAME" >&2 exit 3 ;; esac :

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  • How can I change the default location/action of 'Open Outlook Data File' in Outlook 2010?

    - by Chadddada
    I have recently deployed a Remote Desktop Host server that functions as a remote Microsoft Office 2010 work space for users. In part of the locking down of this server I have installed all programs on the D: drive and, through the use of Group Policy, hidden all the drives on the server from standard users. In addition to hiding these drives I am not allowing users to save anything locally (on the server) or open Libraries. However one of the functions of the server is to provide the Outlook client. Often users will have the .PST file stored on a network location and want to open this in Outlook. Can I change the default action or location that File Open Open Outlook Data File looks or tries to pull the file from? The default location seems to be under Users / Libraries. When click 'Open' you get a warning: This operation has been cancelled due to restrictions in effect on this computer. Clicking OK drops the user into a small menu that shows attached network drives under Computer. Can I instead have the 'Open' click drop the users in a defined network drive or just open computer and allow them to select a share? I don't want them to see the error message. A solution that looks to have been used for Office 2000/03 is: Key: HKEY_CURRENT_USER\Software\Microsoft\Office\<version>\Outlook Value name: ForceOSTPath Value type: REG_EXPAND_SZ Value: path to your storage folder I am not sure if there is a better way to do this now OR if this even works with Office 2010.

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  • umask seems to vary by user

    - by paullb
    I've got a development Ubuntu system for which I have several users: myself (with full sudo) and about 5 other users. (I've set up the system so everything in this respect is still at its default setting) I'm trying to set the system up so that multiple people can collaborate in a single directory by using grouing and I want the default permissions to be 664. However when some users edit files the permissions were 644. After a lot of investigating most users have a umask (checked at the prompt) of 0002 and when they create files they are 664 (as expected) but there are 2 (myself and one other) who have 0022 umask (so the files that come out are 644 and nobody else can write to them). I've looked everywhere but can't figure out why a couple users wind up with a different umask e.g. there is nothing the .bash_profile or anything like that) Any ideas for the source of the discrepancy? /etc/bashrc if [ $UID -gt 199 ] && [ "`id -gn`" = "`id -un`" ]; then umask 002 else umask 022 fi /etc/profile if [ $UID -gt 199 ] && [ "`id -gn`" = "`id -un`" ]; then umask 002 else umask 022 fi EDIT: My (bad) ~/.bashrc # .bashrc # Source global definitions if [ -f /etc/bashrc ]; then . /etc/bashrc fi # User specific aliases and functions export LANG=en_US.utf8 Other user (good) .bashrc # .bashrc # Source global definitions if [ -f /etc/bashrc ]; then . /etc/bashrc fi # User specific aliases and functions

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  • Does Guest WiFi on an Access Point make any sense? [migrated]

    - by Jason
    I have a Belkin WiFi Router which offers a feature of a secondary Guest Access WiFi network. Of course, the idea is that the Guest network doesn't have access to the computers/devices on the main network. I also have a Comcast-issues Cable Modem/Router device with mutliple wired ports, but no WiFi-capabilities. I prefer to only run one router/DHCP/NAT instead of both the Comcast Router and the Belkin Router, so I can disable the Routing functions of the Belkin and allow the Comcast Router to But if I disable the Routing functions of the Belkin device, the Guest WiFi network is still available. Is this configuration just as secure as when the Belkin acts as a Router? I guess the question comes down to this: Do Guest WiFi's provide security by 1) only allowing requests to IPs found in-front of the device, or do they work by 2) disallowing requests to IPs on the same subnet? 1) Would mean that Guest WiFi on an access point provides no benefit 2) Would mean that the Guest WiFi functionality can work even if the device is just an access point. Or maybe something else entirely?

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  • sudoer scheme to allow useful access to another web developer yet retain future control of a virtual

    - by Tchalvak
    Background: Virtual Private Server I have a virtual private server that I'm looking to host multiple websites on, and provide access to another web developer. I don't care about putting too many constraints on him, though I wouldn't mind isolating the site that he'll be developing from other sites on the server that I will develop. The problem: retain control Mainly what I want is to make sure that I retain control over the server in the future. I want to reserve the ability to create/promote/demote and other administrative functions that don't deal with web software. If I make him an admin, he can sudo su - and become root and remove root control from me, for example. I need him not to be able to: take away other admin permissions change the root password have control over other security/administrative functions I would like him to still be able to: install software (through apt-get) restart apache access mysql configure mysql/apache reboot edit web development configuration type files in /etc/ Other Standard Setups would be happily considered I've never really set up a good sudoers file, so simple example setups would be very useful, even if they're only somewhat similar to the settings that I'm hoping for above. Edit: I have not yet finalized permissions, so standard, useful sudo setups are certainly an option, the lists above are more what I'm hoping I can do, I don't know that that setup can be done. I'm sure that people have solved this type of problem before somehow, though, and I'd like to go with something somewhat tested as opposed to something I've homegrown.

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  • How can I automate or script daily downloads for any new anti- virus databases, and then have the program scan my drive?

    - by Macgrimm
    Howdy all Super Users" I humbly ask if any Super User can direct this long time, gray haired Apple Tech in the right direction on this issue. I believe there probably are many ways to skin this cat. But I am looking to find simply the best, most unattended way to get it done. Any help will be greatly appreciated. also (I know there are much better softwares out there for the Mac so please don't go there! The politics of this company dictate which Anti virus we have to use) anyway without any further wait: basically I am trying to automate 2 very important functions of Mc'Afee anti-virus for Mac. First I want to automate the process of retrieving new virus definition files, and second I want to automate the process of scanning for viruses. It turns out that Using Mc'Afee Anti-Virus for the Mac are both manual functions. And they left up to the user (per user account) to perform. Depending on all of about 150 MAc users to perform these 2 tasks themselves is around 65% compliance. My question then is: If I wanted to use the command line such as (open /Applications/McAfee\ Security.app) It will open up the Security Console. But how can I make command Mc'Afee go out and grab the definition files and scan the computer? I have to admit I am at a crossroad and Macaltimers has set in. I would really appreciate it if any of you "Super ~ Users" can help me out with this MacAltimers loss of how to what to do. Thanks to All up Front Macgrimm

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  • Receiving and processing SMS messages through a script?

    - by ShankarG
    I am attempting to setup a system to receive and process SMS messages automatically. The system is intended for use in a context (an unfunded migrant workers' union in India) where both finances and sysadmin skills are extremely constrained (I would be the only person, in the near future, who would be administering the system). The intention is to make some functions - registration of members, generation of ID cards, communication of alerts and other information - easier. However, for receiving and sending SMS, I have not been able to find any email to SMS or other kind of gateway that functions in India. Perhaps there is one (edit: apparently Clickatell does have an India service, but the prices appear astronomical). If not, can one rely on a USB mobile modem (such as those provided by many mobile providers in India)? It seems like, with utilities such as gammu or bitpim, SMS operations on such a modem could be scripted. Is this actually feasible, though? Thanks in advance for your thoughts and suggestions. edit: Original first question removed since the two questions had little to do with each other. The original first question has been asked separately here

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  • file doesn't open, running outside of debugger results in seg fault (c++)

    - by misterich
    Hello (and thanks in advance) I'm in a bit of a quandry, I cant seem to figure out why I'm seg faulting. A couple of notes: It's for a course -- and sadly I am required to use use C-strings instead of std::string. Please dont fix my code (I wont learn that way and I will keep bugging you). please just point out the flaws in my logic and suggest a different function/way. platform: gcc version 4.4.1 on Suse Linux 11.2 (2.6.31 kernel) Here's the code main.cpp: // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C/C++ Std Library) #include <cstdlib> /// EXIT_SUCCESS, EXIT_FAILURE #include <iostream> /// cin, cout, ifstream #include <cassert> /// assert // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "dict.h" /// Header for the dictionary class // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR CONSTANTS #define ENTER '\n' /// Used to accept new lines, quit program. #define SPACE ' ' /// One way to end the program // /////////////////////////////////////////////////////////////////////////////////// // CUSTOM DATA TYPES /// File Namespace -- keep it local namespace { /// Possible program prompts to display for the user. enum FNS_Prompts { fileName_, /// prints out the name of the file noFile_, /// no file was passed to the program tooMany_, /// more than one file was passed to the program noMemory_, /// Not enough memory to use the program usage_, /// how to use the program word_, /// ask the user to define a word. notFound_, /// the word is not in the dictionary done_, /// the program is closing normally }; } // /////////////////////////////////////////////////////////////////////////////////// // Namespace using namespace std; /// Nothing special in the way of namespaces // /////////////////////////////////////////////////////////////////////////////////// // FUNCTIONS /** prompt() prompts the user to do something, uses enum Prompts for parameter. */ void prompt(FNS_Prompts msg /** determines the prompt to use*/) { switch(msg) { case fileName_ : { cout << ENTER << ENTER << "The file name is: "; break; } case noFile_ : { cout << ENTER << ENTER << "...Sorry, a dictionary file is needed. Try again." << endl; break; } case tooMany_ : { cout << ENTER << ENTER << "...Sorry, you can only specify one dictionary file. Try again." << endl; break; } case noMemory_ : { cout << ENTER << ENTER << "...Sorry, there isn't enough memory available to run this program." << endl; break; } case usage_ : { cout << "USAGE:" << endl << " lookup.exe [dictionary file name]" << endl << endl; break; } case done_ : { cout << ENTER << ENTER << "like Master P says, \"Word.\"" << ENTER << endl; break; } case word_ : { cout << ENTER << ENTER << "Enter a word in the dictionary to get it's definition." << ENTER << "Enter \"?\" to get a sorted list of all words in the dictionary." << ENTER << "... Press the Enter key to quit the program: "; break; } case notFound_ : { cout << ENTER << ENTER << "...Sorry, that word is not in the dictionary." << endl; break; } default : { cout << ENTER << ENTER << "something passed an invalid enum to prompt(). " << endl; assert(false); /// something passed in an invalid enum } } } /** useDictionary() uses the dictionary created by createDictionary * - prompts user to lookup a word * - ends when the user enters an empty word */ void useDictionary(Dictionary &d) { char *userEntry = new char; /// user's input on the command line if( !userEntry ) // check the pointer to the heap { cout << ENTER << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } do { prompt(word_); // test code cout << endl << "----------------------------------------" << endl << "Enter something: "; cin.getline(userEntry, INPUT_LINE_MAX_LEN, ENTER); cout << ENTER << userEntry << endl; }while ( userEntry[0] != NIL && userEntry[0] != SPACE ); // GARBAGE COLLECTION delete[] userEntry; } /** Program Entry * Reads in the required, single file from the command prompt. * - If there is no file, state such and error out. * - If there is more than one file, state such and error out. * - If there is a single file: * - Create the database object * - Populate the database object * - Prompt the user for entry * main() will return EXIT_SUCCESS upon termination. */ int main(int argc, /// the number of files being passed into the program char *argv[] /// pointer to the filename being passed into tthe program ) { // EXECUTE /* Testing code * / char tempFile[INPUT_LINE_MAX_LEN] = {NIL}; cout << "enter filename: "; cin.getline(tempFile, INPUT_LINE_MAX_LEN, '\n'); */ // uncomment after successful debugging if(argc <= 1) { prompt(noFile_); prompt(usage_); return EXIT_FAILURE; /// no file was passed to the program } else if(argc > 2) { prompt(tooMany_); prompt(usage_); return EXIT_FAILURE; /// more than one file was passed to the program } else { prompt(fileName_); cout << argv[1]; // print out name of dictionary file if( !argv[1] ) { prompt(noFile_); prompt(usage_); return EXIT_FAILURE; /// file does not exist } /* file.open( argv[1] ); // open file numEntries >> in.getline(file); // determine number of dictionary objects to create file.close(); // close file Dictionary[ numEntries ](argv[1]); // create the dictionary object */ // TEMPORARY FILE FOR TESTING!!!! //Dictionary scrabble(tempFile); Dictionary scrabble(argv[1]); // creaate the dicitonary object //*/ useDictionary(scrabble); // prompt the user, use the dictionary } // exit return EXIT_SUCCESS; /// terminate program. } Dict.h/.cpp #ifndef DICT_H #define DICT_H // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (Custom header files) #include "entry.h" /// class for dictionary entries // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define INPUT_LINE_MAX_LEN 256 /// Maximum length of each line in the dictionary file class Dictionary { public : // // Do NOT modify the public section of this class // typedef void (*WordDefFunc)(const char *word, const char *definition); Dictionary( const char *filename ); ~Dictionary(); const char *lookupDefinition( const char *word ); void forEach( WordDefFunc func ); private : // // You get to provide the private members // // VARIABLES int m_numEntries; /// stores the number of entries in the dictionary Entry *m_DictEntry_ptr; /// points to an array of class Entry // Private Functions }; #endif ----------------------------------- // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C/C++ Std Library) #include <iostream> /// cout, getline #include <fstream> // ifstream #include <cstring> /// strchr // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "dict.h" /// Header file required by assignment //#include "entry.h" /// Dicitonary Entry Class // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define COMMA ',' /// Delimiter for file #define ENTER '\n' /// Carriage return character #define FILE_ERR_MSG "The data file could not be opened. Program will now terminate." #pragma warning(disable : 4996) /// turn off MS compiler warning about strcpy() // /////////////////////////////////////////////////////////////////////////////////// // Namespace reference using namespace std; // /////////////////////////////////////////////////////////////////////////////////// // PRIVATE MEMBER FUNCTIONS /** * Sorts the dictionary entries. */ /* static void sortDictionary(?) { // sort through the words using qsort } */ /** NO LONGER NEEDED?? * parses out the length of the first cell in a delimited cell * / int getWordLength(char *str /// string of data to parse ) { return strcspn(str, COMMA); } */ // /////////////////////////////////////////////////////////////////////////////////// // PUBLIC MEMBER FUNCTIONS /** constructor for the class * - opens/reads in file * - creates initializes the array of member vars * - creates pointers to entry objects * - stores pointers to entry objects in member var * - ? sort now or later? */ Dictionary::Dictionary( const char *filename ) { // Create a filestream, open the file to be read in ifstream dataFile(filename, ios::in ); /* if( dataFile.fail() ) { cout << FILE_ERR_MSG << endl; exit(EXIT_FAILURE); } */ if( dataFile.is_open() ) { // read first line of data // TEST CODE in.getline(dataFile, INPUT_LINE_MAX_LEN) >> m_numEntries; // TEST CODE char temp[INPUT_LINE_MAX_LEN] = {NIL}; // TEST CODE dataFile.getline(temp,INPUT_LINE_MAX_LEN,'\n'); dataFile >> m_numEntries; /** Number of terms in the dictionary file * \todo find out how many lines in the file, subtract one, ingore first line */ //create the array of entries m_DictEntry_ptr = new Entry[m_numEntries]; // check for valid memory allocation if( !m_DictEntry_ptr ) { cout << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } // loop thru each line of the file, parsing words/def's and populating entry objects for(int EntryIdx = 0; EntryIdx < m_numEntries; ++EntryIdx) { // VARIABLES char *tempW_ptr; /// points to a temporary word char *tempD_ptr; /// points to a temporary def char *w_ptr; /// points to the word in the Entry object char *d_ptr; /// points to the definition in the Entry int tempWLen; /// length of the temp word string int tempDLen; /// length of the temp def string char tempLine[INPUT_LINE_MAX_LEN] = {NIL}; /// stores a single line from the file // EXECUTE // getline(dataFile, tempLine) // get a "word,def" line from the file dataFile.getline(tempLine, INPUT_LINE_MAX_LEN); // get a "word,def" line from the file // Parse the string tempW_ptr = tempLine; // point the temp word pointer at the first char in the line tempD_ptr = strchr(tempLine, COMMA); // point the def pointer at the comma *tempD_ptr = NIL; // replace the comma with a NIL ++tempD_ptr; // increment the temp def pointer // find the string lengths... +1 to account for terminator tempWLen = strlen(tempW_ptr) + 1; tempDLen = strlen(tempD_ptr) + 1; // Allocate heap memory for the term and defnition w_ptr = new char[ tempWLen ]; d_ptr = new char[ tempDLen ]; // check memory allocation if( !w_ptr && !d_ptr ) { cout << MEM_ERR_MSG << endl; exit(EXIT_FAILURE); } // copy the temp word, def into the newly allocated memory and terminate the strings strcpy(w_ptr,tempW_ptr); w_ptr[tempWLen] = NIL; strcpy(d_ptr,tempD_ptr); d_ptr[tempDLen] = NIL; // set the pointers for the entry objects m_DictEntry_ptr[ EntryIdx ].setWordPtr(w_ptr); m_DictEntry_ptr[ EntryIdx ].setDefPtr(d_ptr); } // close the file dataFile.close(); } else { cout << ENTER << FILE_ERR_MSG << endl; exit(EXIT_FAILURE); } } /** * cleans up dynamic memory */ Dictionary::~Dictionary() { delete[] m_DictEntry_ptr; /// thou shalt not have memory leaks. } /** * Looks up definition */ /* const char *lookupDefinition( const char *word ) { // print out the word ---- definition } */ /** * prints out the entire dictionary in sorted order */ /* void forEach( WordDefFunc func ) { // to sort before or now.... that is the question } */ Entry.h/cpp #ifndef ENTRY_H #define ENTRY_H // /////////////////////////////////////////////////////////////////////////////////// // INCLUDES (C++ Std lib) #include <cstdlib> /// EXIT_SUCCESS, NULL // /////////////////////////////////////////////////////////////////////////////////// // PRE-PROCESSOR MACROS #define NIL '\0' /// C-String terminator #define MEM_ERR_MSG "Memory allocation has failed. Program will now terminate." // /////////////////////////////////////////////////////////////////////////////////// // CLASS DEFINITION class Entry { public: Entry(void) : m_word_ptr(NULL), m_def_ptr(NULL) { /* default constructor */ }; void setWordPtr(char *w_ptr); /// sets the pointer to the word - only if the pointer is empty void setDefPtr(char *d_ptr); /// sets the ponter to the definition - only if the pointer is empty /// returns what is pointed to by the word pointer char getWord(void) const { return *m_word_ptr; } /// returns what is pointed to by the definition pointer char getDef(void) const { return *m_def_ptr; } private: char *m_word_ptr; /** points to a dictionary word */ char *m_def_ptr; /** points to a dictionary definition */ }; #endif -------------------------------------------------- // /////////////////////////////////////////////////////////////////////////////////// // DEPENDENCIES (custom header files) #include "entry.h" /// class header file // /////////////////////////////////////////////////////////////////////////////////// // PUBLIC FUNCTIONS /* * only change the word member var if it is in its initial state */ void Entry::setWordPtr(char *w_ptr) { if(m_word_ptr == NULL) { m_word_ptr = w_ptr; } } /* * only change the def member var if it is in its initial state */ void Entry::setDefPtr(char *d_ptr) { if(m_def_ptr == NULL) { m_word_ptr = d_ptr; } }

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  • Dealing with external processes

    - by Jesse Aldridge
    I've been working on a gui app that needs to manage external processes. Working with external processes leads to a lot of issues that can make a programmer's life difficult. I feel like maintenence on this app is taking an unacceptably long time. I've been trying to list the things that make working with external processes difficult so that I can come up with ways of mitigating the pain. This kind of turned into a rant which I thought I'd post here in order to get some feedback and to provide some guidance to anybody thinking about sailing into these very murky waters. Here's what I've got so far: Output from the child can get mixed up with output from the parent. This can make both outputs misleading and hard to read. It can be hard to tell what came from where. It becomes harder to figure out what's going on when things are asynchronous. Here's a contrived example: import textwrap, os, time from subprocess import Popen test_path = 'test_file.py' with open(test_path, 'w') as file: file.write(textwrap.dedent(''' import time for i in range(3): print 'Hello %i' % i time.sleep(1)''')) proc = Popen('python -B "%s"' % test_path) for i in range(3): print 'Hello %i' % i time.sleep(1) os.remove(test_path) I guess I could have the child process write its output to a file. But it can be annoying to have to open up a file every time I want to see the result of a print statement. If I have code for the child process I could add a label, something like print 'child: Hello %i', but it can be annoying to do that for every print. And it adds some noise to the output. And of course I can't do it if I don't have access to the code. I could manually manage the process output. But then you open up a huge can of worms with threads and polling and stuff like that. A simple solution is to treat processes like synchronous functions, that is, no further code executes until the process completes. In other words, make the process block. But that doesn't work if you're building a gui app. Which brings me to the next problem... Blocking processes cause the gui to become unresponsive. import textwrap, sys, os from subprocess import Popen from PyQt4.QtGui import * from PyQt4.QtCore import * test_path = 'test_file.py' with open(test_path, 'w') as file: file.write(textwrap.dedent(''' import time for i in range(3): print 'Hello %i' % i time.sleep(1)''')) app = QApplication(sys.argv) button = QPushButton('Launch process') def launch_proc(): # Can't move the window until process completes proc = Popen('python -B "%s"' % test_path) proc.communicate() button.connect(button, SIGNAL('clicked()'), launch_proc) button.show() app.exec_() os.remove(test_path) Qt provides a process wrapper of its own called QProcess which can help with this. You can connect functions to signals to capture output relatively easily. This is what I'm currently using. But I'm finding that all these signals behave suspiciously like goto statements and can lead to spaghetti code. I think I want to get sort-of blocking behavior by having the 'finished' signal from QProcess call a function containing all the code that comes after the process call. I think that should work but I'm still a bit fuzzy on the details... Stack traces get interrupted when you go from the child process back to the parent process. If a normal function screws up, you get a nice complete stack trace with filenames and line numbers. If a subprocess screws up, you'll be lucky if you get any output at all. You end up having to do a lot more detective work everytime something goes wrong. Speaking of which, output has a way of disappearing when dealing external processes. Like if you run something via the windows 'cmd' command, the console will pop up, execute the code, and then disappear before you have a chance to see the output. You have to pass the /k flag to make it stick around. Similar issues seem to crop up all the time. I suppose both problems 3 and 4 have the same root cause: no exception handling. Exception handling is meant to be used with functions, it doesn't work with processes. Maybe there's some way to get something like exception handling for processes? I guess that's what stderr is for? But dealing with two different streams can be annoying in itself. Maybe I should look into this more... Processes can hang and stick around in the background without you realizing it. So you end up yelling at your computer cuz it's going so slow until you finally bring up your task manager and see 30 instances of the same process hanging out in the background. Also, hanging background processes can interefere with other instances of the process in various fun ways, such as causing permissions errors by holding a handle to a file or someting like that. It seems like an easy solution to this would be to have the parent process kill the child process on exit if the child process didn't close itself. But if the parent process crashes, cleanup code might not get called and the child can be left hanging. Also, if the parent waits for the child to complete, and the child is in an infinite loop or something, you can end up with two hanging processes. This problem can tie in to problem 2 for extra fun, causing your gui to stop responding entirely and force you to kill everything with the task manager. F***ing quotes Parameters often need to be passed to processes. This is a headache in itself. Especially if you're dealing with file paths. Say... 'C:/My Documents/whatever/'. If you don't have quotes, the string will often be split at the space and interpreted as two arguments. If you need nested quotes you can use ' and ". But if you need to use more than two layers of quotes, you have to do some nasty escaping, for example: "cmd /k 'python \'path 1\' \'path 2\''". A good solution to this problem is passing parameters as a list rather than as a single string. Subprocess allows you to do this. Can't easily return data from a subprocess. You can use stdout of course. But what if you want to throw a print in there for debugging purposes? That's gonna screw up the parent if it's expecting output formatted a certain way. In functions you can print one string and return another and everything works just fine. Obscure command-line flags and a crappy terminal based help system. These are problems I often run into when using os level apps. Like the /k flag I mentioned, for holding a cmd window open, who's idea was that? Unix apps don't tend to be much friendlier in this regard. Hopefully you can use google or StackOverflow to find the answer you need. But if not, you've got a lot of boring reading and frusterating trial and error to do. External factors. This one's kind of fuzzy. But when you leave the relatively sheltered harbor of your own scripts to deal with external processes you find yourself having to deal with the "outside world" to a much greater extent. And that's a scary place. All sorts of things can go wrong. Just to give a random example: the cwd in which a process is run can modify it's behavior. There are probably other issues, but those are the ones I've written down so far. Any other snags you'd like to add? Any suggestions for dealing with these problems?

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  • How to Configure Windows Machine to Allow File Sharing with DNS Alias

    - by Michael Ferrante
    I have not seen a single article posted anywhere online that brings together all the settings one would need to do to make this work properly on Windows, so I thought I would post it here. To facilitate failover schemes, a common technique is to use DNS CNAME records (DNS Aliases) for different machine roles. Then instead of changing the Windows computername of the actual machine name, one can switch a DNS record to point to a new host. This can work on Microsoft Windows machines, but to make it work with file sharing the following configuration steps need to be taken. Outline The Problem The Solution Allowing other machines to use filesharing via the DNS Alias (DisableStrictNameChecking) Allowing server machine to use filesharing with itself via the DNS Alias (BackConnectionHostNames) Providing browse capabilities for multiple NetBIOS names (OptionalNames) Register the Kerberos service principal names (SPNs) for other Windows functions like Printing (setspn) References 1. The Problem On Windows machines, file sharing can work via the computer name, with or without full qualification, or by the IP Address. By default, however, filesharing will not work with arbitrary DNS aliases. To enable filesharing and other Windows services to work with DNS aliases, you must make registry changes as detailed below and reboot the machine. 2. The Solution Allowing other machines to use filesharing via the DNS Alias (DisableStrictNameChecking) This change alone will allow other machines on the network to connect to the machine using any arbitrary hostname. (However this change will not allow a machine to connect to itself via a hostname, see BackConnectionHostNames below). Edit the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters and add a value DisableStrictNameChecking of type DWORD set to 1. Allowing server machine to use filesharing with itself via the DNS Alias (BackConnectionHostNames) This change is necessary for a DNS alias to work with filesharing from a machine to find itself. This creates the Local Security Authority host names that can be referenced in an NTLM authentication request. To do this, follow these steps for all the nodes on the client computer: To the registry subkey HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\MSV1_0, add new Multi-String Value BackConnectionHostNames In the Value data box, type the CNAME or the DNS alias, that is used for the local shares on the computer, and then click OK. Note: Type each host name on a separate line. Providing browse capabilities for multiple NetBIOS names (OptionalNames) Allows ability to see the network alias in the network browse list. Edit the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters and add a value OptionalNames of type Multi-String Add in a newline delimited list of names that should be registered under the NetBIOS browse entries Names should match NetBIOS conventions (i.e. not FQDN, just hostname) Register the Kerberos service principal names (SPNs) for other Windows functions like Printing (setspn) NOTE: Should not need to do this for basic functions to work, documented here for completeness. We had one situation in which the DNS alias was not working because there was an old SPN record interfering, so if other steps aren't working check if there are any stray SPN records. You must register the Kerberos service principal names (SPNs), the host name, and the fully-qualified domain name (FQDN) for all the new DNS alias (CNAME) records. If you do not do this, a Kerberos ticket request for a DNS alias (CNAME) record may fail and return the error code KDC_ERR_S_SPRINCIPAL_UNKNOWN. To view the Kerberos SPNs for the new DNS alias records, use the Setspn command-line tool (setspn.exe). The Setspn tool is included in Windows Server 2003 Support Tools. You can install Windows Server 2003 Support Tools from the Support\Tools folder of the Windows Server 2003 startup disk. How to use the tool to list all records for a computername: setspn -L computername To register the SPN for the DNS alias (CNAME) records, use the Setspn tool with the following syntax: setspn -A host/your_ALIAS_name computername setspn -A host/your_ALIAS_name.company.com computername 3. References All the Microsoft references work via: http://support.microsoft.com/kb/ Connecting to SMB share on a Windows 2000-based computer or a Windows Server 2003-based computer may not work with an alias name Covers the basics of making file sharing work properly with DNS alias records from other computers to the server computer. KB281308 Error message when you try to access a server locally by using its FQDN or its CNAME alias after you install Windows Server 2003 Service Pack 1: "Access denied" or "No network provider accepted the given network path" Covers how to make the DNS alias work with file sharing from the file server itself. KB926642 How to consolidate print servers by using DNS alias (CNAME) records in Windows Server 2003 and in Windows 2000 Server Covers more complex scenarios in which records in Active Directory may need to be updated for certain services to work properly and for browsing for such services to work properly, how to register the Kerberos service principal names (SPNs). KB870911 Distributed File System update to support consolidation roots in Windows Server 2003 Covers even more complex scenarios with DFS (discusses OptionalNames). KB829885

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  • Using windows command line from Pascal

    - by Jordan
    I'm trying to use some windows command line tools from within a short Pascal program. To make it easier, I'm writing a function called DoShell which takes a command line string as an argument and returns a record type called ShellResult, with one field for the process's exitcode and one field for the process's output text. I'm having major problems with some standard library functions not working as expected. The DOS Exec() function is not actually carrying out the command i pass to it. The Reset() procedure gives me a runtime error RunError(2) unless i set the compiler mode {I-}. In that case i get no runtime error, but the Readln() functions that i use on that file afterwards don't actually read anything, and furthermore the Writeln() functions used after that point in the code execution do nothing as well. Here's the source code of my program so far. I'm using Lazarus 0.9.28.2 beta, with Free Pascal Compiler 2.24 program project1; {$mode objfpc}{$H+} uses Classes, SysUtils, StrUtils, Dos { you can add units after this }; {$IFDEF WINDOWS}{$R project1.rc}{$ENDIF} type ShellResult = record output : AnsiString; exitcode : Integer; end; function DoShell(command: AnsiString): ShellResult; var exitcode: Integer; output: AnsiString; exepath: AnsiString; exeargs: AnsiString; splitat: Integer; F: Text; readbuffer: AnsiString; begin //Initialize variables exitcode := 0; output := ''; exepath := ''; exeargs := ''; splitat := 0; readbuffer := ''; Result.exitcode := 0; Result.output := ''; //Split command for processing splitat := NPos(' ', command, 1); exepath := Copy(command, 1, Pred(splitat)); exeargs := Copy(command, Succ(splitat), Length(command)); //Run command and put output in temporary file Exec(FExpand(exepath), exeargs + ' __output'); exitcode := DosExitCode(); //Get output from file Assign(F, '__output'); Reset(F); Repeat Readln(F, readbuffer); output := output + readbuffer; readbuffer := ''; Until Eof(F); //Set Result Result.exitcode := exitcode; Result.output := output; end; var I : AnsiString; R : ShellResult; begin Writeln('Enter a command line to run.'); Readln(I); R := DoShell(I); Writeln('Command Exit Code:'); Writeln(R.exitcode); Writeln('Command Output:'); Writeln(R.output); end.

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  • How to use objects as modules/functors in Scala?

    - by Jeff
    Hi. I want to use object instances as modules/functors, more or less as shown below: abstract class Lattice[E] extends Set[E] { val minimum: E val maximum: E def meet(x: E, y: E): E def join(x: E, y: E): E def neg(x: E): E } class Calculus[E](val lat: Lattice[E]) { abstract class Expr case class Var(name: String) extends Expr {...} case class Val(value: E) extends Expr {...} case class Neg(e1: Expr) extends Expr {...} case class Cnj(e1: Expr, e2: Expr) extends Expr {...} case class Dsj(e1: Expr, e2: Expr) extends Expr {...} } So that I can create a different calculus instance for each lattice (the operations I will perform need the information of which are the maximum and minimum values of the lattice). I want to be able to mix expressions of the same calculus but not be allowed to mix expressions of different ones. So far, so good. I can create my calculus instances, but problem is that I can not write functions in other classes that manipulate them. For example, I am trying to create a parser to read expressions from a file and return them; I also was trying to write an random expression generator to use in my tests with ScalaCheck. Turns out that every time a function generates an Expr object I can't use it outside the function. Even if I create the Calculus instance and pass it as an argument to the function that will in turn generate the Expr objects, the return of the function is not recognized as being of the same type of the objects created outside the function. Maybe my english is not clear enough, let me try a toy example of what I would like to do (not the real ScalaCheck generator, but close enough). def genRndExpr[E](c: Calculus[E], level: Int): Calculus[E]#Expr = { if (level > MAX_LEVEL) { val select = util.Random.nextInt(2) select match { case 0 => genRndVar(c) case 1 => genRndVal(c) } } else { val select = util.Random.nextInt(3) select match { case 0 => new c.Neg(genRndExpr(c, level+1)) case 1 => new c.Dsj(genRndExpr(c, level+1), genRndExpr(c, level+1)) case 2 => new c.Cnj(genRndExpr(c, level+1), genRndExpr(c, level+1)) } } } Now, if I try to compile the above code I get lots of error: type mismatch; found : plg.mvfml.Calculus[E]#Expr required: c.Expr case 0 = new c.Neg(genRndExpr(c, level+1)) And the same happens if I try to do something like: val boolCalc = new Calculus(Bool) val e1: boolCalc.Expr = genRndExpr(boolCalc) Please note that the generator itself is not of concern, but I will need to do similar things (i.e. create and manipulate calculus instance expressions) a lot on the rest of the system. Am I doing something wrong? Is it possible to do what I want to do? Help on this matter is highly needed and appreciated. Thanks a lot in advance. After receiving an answer from Apocalisp and trying it. Thanks a lot for the answer, but there are still some issues. The proposed solution was to change the signature of the function to: def genRndExpr[E, C <: Calculus[E]](c: C, level: Int): C#Expr I changed the signature for all the functions involved: getRndExpr, getRndVal and getRndVar. And I got the same error message everywhere I call these functions and got the following error message: error: inferred type arguments [Nothing,C] do not conform to method genRndVar's type parameter bounds [E,C genRndVar(c) Since the compiler seemed to be unable to figure out the right types I changed all function call to be like below: case 0 => new c.Neg(genRndExpr[E,C](c, level+1)) After this, on the first 2 function calls (genRndVal and genRndVar) there were no compiling error, but on the following 3 calls (recursive calls to genRndExpr), where the return of the function is used to build a new Expr object I got the following error: error: type mismatch; found : C#Expr required: c.Expr case 0 = new c.Neg(genRndExpr[E,C](c, level+1)) So, again, I'm stuck. Any help will be appreciated.

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  • JQuery get attr value from ajax loaded page

    - by Paolo Rossi
    In my index.php I've a ajax pager that load a content page (paginator.php). index.php <script type='text/javascript' src='js/jquery-1.11.1.min.js'></script> <script type='text/javascript' src='js/paginator.js'></script> <script type='text/javascript' src='js/functions.js'></script> <!-- Add fancyBox --> <script type="text/javascript" src="js/jquery.fancybox.pack.js?v=2.1.5"></script> <html> <div id="content"></div> paginator.js $(function() { var pageurl = 'paginator.php'; //Initialise the table at the first run $( '#content' ).load( pageurl, { pag: 1 }, function() { //animation(); }); //Page navigation click $( document ).on( 'click', 'li.goto', function() { //Get the id of clicked li var pageNum = $( this ).attr( 'id' ); $( '#content' ).load( pageurl, { pag: pageNum }, function() { //animation(); }); }); }); /* END */ paginator.php <ul><li>..etc </ul> ... ... <a id='test' vid='123'>get the id</a> <a id='test2' url='somepage.php'>open fancybox</a> I would like to take a variable of the loaded page (paginator.php) in this way but unfortunately I can not. functions.js $(function() { $('#test' ).click(function(e) { var id = $('#test').attr('vid'); alert ("vid is " + vid); }); }); /* END */ In this case popup not appear. I tried with add fancybox in my functions.js. Dialog box appear but the url attr is not taken. var url = $('#test2').attr('url'); $('#test').fancybox({ 'href' : url, 'width' : 100, 'height' : 100, 'autoScale' : false, 'transitionIn' : 'none', 'transitionOut' : 'none', 'type' : 'iframe', 'fitToView' : true, 'autoSize' : false }); In other scenarios, without having the page loaded, I can do it, but in this case the behavior is different. How could I do this? thanks EDIT my goal is to open a dialog (fancybox) taking a variable from the loaded page EDIT2 I tried in this way paginator.php <a id="test" vid="1234">click me</a> paginator.js //Initialise the table at the first run $( '#content' ).load( pageurl, { pag: 1 }, function() { hide_anim(); popup(); }); //Page navigation click $( document ).on( 'click', 'li.goto', function() { //Get the id of clicked li var pageNum = $( this ).attr( 'id' ); $( '#content' ).load( pageurl, { pag: pageNum }, function() { hide_anim(); popup(); }); }) function.js function popup() { $('#test' ).click(function(e) { e.preventDefault(); var vid = $('#test').attr('vid'); alert ("vid is " + vid); }); } But popup not appear...

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  • Converting OCaml to F#: F# equivelent of Pervasives at_exit

    - by Guy Coder
    I am converting the OCaml Format module to F# and tracked a problem back to a use of the OCaml Pervasives at_exit. val at_exit : (unit -> unit) -> unit Register the given function to be called at program termination time. The functions registered with at_exit will be called when the program executes exit, or terminates, either normally or because of an uncaught exception. The functions are called in "last in, first out" order: the function most recently added with at_exit is called first. In the process of conversion I commented out the line as the compiler did not flag it as being needed and I was not expecting an event in the code. I checked the FSharp.PowerPack.Compatibility.PervasivesModule for at_exit using VS Object Browser and found none. I did find how to run code "at_exit"? and How do I write an exit handler for an F# application? The OCaml line is at_exit print_flush with print_flush signature: val print_flush : (unit -> unit) Also in looking at the use of it during a debug session of the OCaml code, it looks like at_exit is called both at the end of initialization and at the end of each use of a call to the module. Any suggestions, hints on how to do this. This will be my first event in F#. EDIT Here is some of what I have learned about the Format module that should shed some light on the problem. The Format module is a library of functions for basic pretty printer commands of simple OCaml values such as int, bool, string. The format module has commands like print_string, but also some commands to say put the next line in a bounded box, think new set of left and right margins. So one could write: print_string "Hello" or open_box 0; print_string "<<"; open_box 0; print_string "p \/ q ==> r"; close_box(); print_string ">>"; close_box() The commands such as open_box and print_string are handled by a loop that interprets the commands and then decides wither to print on the current line or advance to the next line. The commands are held in a queue and there is a state record to hold mutable values such as left and right margin. The queue and state needs to be primed, which from debugging the test cases against working OCaml code appears to be done at the end of initialization of the module but before the first call is made to any function in the Format module. The queue and state is cleaned up and primed again for the next set of commands by the use of mechanisms for at_exit that recognize that the last matching frame for the initial call to the format modules has been removed thus triggering the call to at_exit which pushes out any remaining command in the queue and re-initializes the queue and state. So the sequencing of the calls to print_flush is critical and appears to be at more than what the OCaml documentation states.

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  • Dynamic obfuscation by self-modifying code

    - by Fallout2
    Hi all, Here what's i am trying to do: assume you have two fonction void f1(int *v) { *v = 55; } void f2(int *v) { *v = 44; } char *template; template = allocExecutablePages(...); char *allocExecutablePages (int pages) { template = (char *) valloc (getpagesize () * pages); if (mprotect (template, getpagesize (), PROT_READ|PROT_EXEC|PROT_WRITE) == -1) { perror (“mprotect”); } } I would like to do a comparison between f1 and f2 (so tell what is identical and what is not) (so get the assembly lines of those function and make a line by line comparison) And then put those line in my template. Is there a way in C to do that? THanks Update Thank's for all you answers guys but maybe i haven't explained my need correctly. basically I'm trying to write a little obfuscation method. The idea consists in letting two or more functions share the same location in memory. A region of memory (which we will call a template) is set up containing some of the machine code bytes from the functions, more specifically, the ones they all have in common. Before a particular function is executed, an edit script is used to patch the template with the necessary machine code bytes to create a complete version of that function. When another function assigned to the same template is about to be executed, the process repeats, this time with a different edit script. To illustrate this, suppose you want to obfuscate a program that contains two functions f1 and f2. The first one (f1) has the following machine code bytes Address Machine code 0 10 1 5 2 6 3 20 and the second one (f2) has Address Machine code 0 10 1 9 2 3 3 20 At obfuscation time, one will replace f1 and f2 by the template Address Machine code 0 10 1 ? 2 ? 3 20 and by the two edit scripts e1 = {1 becomes 5, 2 becomes 6} and e2 = {1 becomes 9, 2 becomes 3}. #include <stdlib.h> #include <string.h> typedef unsigned int uint32; typedef char * addr_t; typedef struct { uint32 offset; char value; } EDIT; EDIT script1[200], script2[200]; char *template; int template_len, script_len = 0; typedef void(*FUN)(int *); int val, state = 0; void f1_stub () { if (state != 1) { patch (script1, script_len, template); state = 1; } ((FUN)template)(&val); } void f2_stub () { if (state != 2) { patch (script2, script_len, template); state = 2; } ((FUN)template)(&val); } int new_main (int argc, char **argv) { f1_stub (); f2_stub (); return 0; } void f1 (int *v) { *v = 99; } void f2 (int *v) { *v = 42; } int main (int argc, char **argv) { int f1SIZE, f2SIZE; /* makeCodeWritable (...); */ /* template = allocExecutablePages(...); */ /* Computed at obfuscation time */ diff ((addr_t)f1, f1SIZE, (addr_t)f2, f2SIZE, script1, script2, &script_len, template, &template_len); /* We hide the proper code */ memset (f1, 0, f1SIZE); memset (f2, 0, f2SIZE); return new_main (argc, argv); } So i need now to write the diff function. that will take the addresses of my two function and that will generate a template with the associated script. So that is why i would like to compare bytes by bytes my two function Sorry for my first post who was not very understandable! Thank you

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  • C++ Serial Port Question

    - by Pfeffer
    Problem: I have a hand held device that scans those graphic color barcodes on all packaging. There is a track device that I can use that will slide the device automatically. This track device functions by taking ascii code through a serial port. I need to get this thing to work in FileMaker on a Mac. So no terminal programs, etc... What I've got so far: I bought a Keyspan USB/Serial adapter. Using a program called ZTerm I was successful in sending commands to the device. Example: "C,7^M^J" I was also able to do the same thing in Terminal using this command: screen /dev/tty.KeySerial1 57600 and then type in the same command above(but when I typed in I just hit Control-M and Control-J for the carriage return and line feed) Now I'm writing a plug-in for FileMaker(in C++ of course). I want to get what I did above happen in C++ so when I install that plug-in in FileMaker I can just call one of those functions and have the whole process take place right there. I'm able to connect to the device, but I can't talk to it. It is not responding to anything. I've tried connecting to the device(successfully) using these: FILE *comport; if ((comport = fopen("/dev/tty.KeySerial1", "w")) == NULL){...} and int fd; fd = open("/dev/tty.KeySerial1", O_RDWR | O_NOCTTY | O_NDELAY); This is what I've tried so far in way of talking to the device: fputs ("C,7^M^J",comport); or fprintf(comport,"C,7^M^J"); or char buffer[] = { 'C' , ',' , '7' , '^' , 'M' , '^' , 'J' }; fwrite (buffer , 1 , sizeof(buffer) , comport ); or fwrite('C,7^M^J', 1, 1, comport); Questions: When I connected to the device from Terminal and using ZTerm, I was able to set my baud rate of 57600. I think that may be why it isn't responding here. But I don't know how to do it here.... Does any one know how to do that? I tried this, but it didn't work: comport->BaudRate = 57600; There are a lot of class solutions out there but they all call these include files like termios.h and stdio.h. I don't have these and, for whatever reason, I can't find them to download. I've downloaded a few examples but there are like 20 files in them and they're all calling other files I can't find(like the ones listed above). Do I need to find these and if so where? I just don't know enough about C++ Is there a website where I can download libraries?? Another solution might be to put those terminal commands in C++. Is there a way to do that? So this has been driving me crazy. I'm not a C++ guy, I only know basic programming concepts. Is anyone out there a C++ expert? I ideally I'd like this to just work using functions I already have, like those fwrite, fputs stuff. Thanks!

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  • How to determine if CNF formula is satisfiable in Scheme?

    - by JJBIRAN
    Program a SCHEME function sat that takes one argument, a CNF formula represented as above. If we had evaluated (define cnf '((a (not b) c) (a (not b) (not d)) (b d))) then evaluating (sat cnf) would return #t, whereas (sat '((a) (not a))) would return (). You should have following two functions to work: (define comp (lambda (lit) ; This function takes a literal as argument and returns the complement literal as the returning value. Examples: (comp 'a) = (not a), and (comp '(not b)) = b. (define consistent (lambda (lit path) This function takes a literal and a list of literals as arguments, and returns #t whenever the complement of the first argument is not a member of the list represented by the 2nd argument; () otherwise. . Now for the sat function. The real searching involves the list of clauses (the CNF formula) and the path that has currently been developed. The sat function should merely invoke the real "workhorse" function, which will have 2 arguments, the current path and the clause list. In the initial call, the current path is of course empty. Hints on sat. (Ignore these at your own risk!) (define sat (lambda (clauselist) ; invoke satpath (define satpath (lambda (path clauselist) ; just returns #t or () ; base cases: ; if we're out of clauses, what then? ; if there are no literals to choose in the 1st clause, what then? ; ; then in general: ; if the 1st literal in the 1st clause is consistent with the ; current path, and if << returns #t, ; then return #t. ; ; if the 1st literal didn't work, then search << ; the CNF formula in which the 1st clause doesn't have that literal Don't make this too hard. My program is a few functions averaging about 2-8 lines each. SCHEME is consise and elegant! The following expressions may help you to test your programs. All but cnf4 are satisfiable. By including them along with your function definitions, the functions themselves are automatically tested and results displayed when the file is loaded. (define cnf1 '((a b c) (c d) (e)) ) (define cnf2 '((a c) (c))) (define cnf3 '((d e) (a))) (define cnf4 '( (a b) (a (not b)) ((not a) b) ((not a) (not b)) ) ) (define cnf5 '((d a) (d b c) ((not a) (not d)) (e (not d)) ((not b)) ((not d) (not e)))) (define cnf6 '((d a) (d b c) ((not a) (not d) (not c)) (e (not c)) ((not b)) ((not d) (not e)))) (write-string "(sat cnf1) ") (write (sat cnf1)) (newline) (write-string "(sat cnf2) ") (write (sat cnf2)) (newline) (write-string "(sat cnf3) ") (write (sat cnf3)) (newline) (write-string "(sat cnf4) ") (write (sat cnf4)) (newline) (write-string "(sat cnf5) ") (write (sat cnf5)) (newline)

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  • Running game, leaving game and continuing animation

    - by Madrusec
    I have been trying to learn some Actionscript recently and have been trying to run an interactive story that at one point turns into an extremel simple shooter game. After the player either wins or looses, then he/she is taken to the rest of the animated story. So I have everything up to the point where the games runs (successfully) but for some reason I am unable to have flash run the rest of the frames, most of which have no code at all. This is the code for scene 1: stop (); import flash.display.MovieClip; import flash.events.MouseEvent; import flash.utils.Timer; import flash.events.TimerEvent; var stoneInGame:uint; var stoneMaker: Timer; var container_mc: MovieClip; var cursor:MovieClip; var score:int; var anxiety:int; var anxiety_mc :MovieClip = new mcAnxiety(); //stage.addChild( anxiety_mc ); function initializeGame():void { stoneInGame = 10; stoneMaker = new Timer(1000, stoneInGame); container_mc = new MovieClip(); addChild(container_mc); container_mc.addChild(anxiety_mc); anxiety_mc.x = 497; anxiety_mc.y = 360; stoneMaker.addEventListener(TimerEvent.TIMER, createStones); stoneMaker.start(); cursor = new Cursor(); addChild(cursor); cursor.enabled = false; Mouse.hide(); stage.addEventListener(MouseEvent.MOUSE_MOVE, dragCursor); score = 0; anxiety = anxiety_mc.totalFrames; anxiety_mc.gotoAndStop(anxiety); } function dragCursor(event:MouseEvent):void { cursor.x = this.mouseX; cursor.y = this.mouseY; } function createStones(event:TimerEvent):void { var stone:MovieClip; stone = new Stone(); stone.x = Math.random() * stage.stageWidth; stone.y = Math.random() * stage.stageHeight; container_mc.addChild(stone); } function increaseScore():void { score ++; if(score >= stoneInGame) { dragCursor.stop(); createStones.stop(); stoneMaker.stop(); trace("you wind!"); } } function decreaseAnxiety():void { anxiety--; if(anxiety <= 0) { stoneMaker.stop(); trace("you lose!"); } else { anxiety_mc.gotoAndStop(anxiety); } increaseScore(); } initializeGame(); So what I tried to do was adding gotoAndPlay() inside both the decreaseAnxiety and increaseScore functions after the trace statements and referenced a frame where I have more keyframes that continue a story. However, Flash just goes back to the beginning of the timeline and I even the functions that change and control the cursor seem to be running. This leads me to believe that I need to make sure that I tell flash o stup running certain functions before jumping to another frame. However, it seems to me that I would still have the same issue and not be able to continue in the timeline. Is there something I am missing? How can I jump out of all this code once the game finishes and simply continue playing the rest of the frames? Any pointers would be greatly appreciated. Thank you

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  • Testing for Adjacent Cells In a Multi-level Grid

    - by Steve
    I'm designing an algorithm to test whether cells on a grid are adjacent or not. The catch is that the cells are not on a flat grid. They are on a multi-level grid such as the one drawn below. Level 1 (Top Level) | - - - - - | | A | B | C | | - - - - - | | D | E | F | | - - - - - | | G | H | I | | - - - - - | Level 2 | -Block A- | -Block B- | | 1 | 2 | 3 | 1 | 2 | 3 | | - - - - - | - - - - - | | 4 | 5 | 6 | 4 | 5 | 6 | ... | - - - - - | - - - - - | | 7 | 8 | 9 | 7 | 8 | 9 | | - - - - - | - - - - - | | -Block D- | -Block E- | | 1 | 2 | 3 | 1 | 2 | 3 | | - - - - - | - - - - - | | 4 | 5 | 6 | 4 | 5 | 6 | ... | - - - - - | - - - - - | | 7 | 8 | 9 | 7 | 8 | 9 | | - - - - - | - - - - - | . . . . . . This diagram is simplified from my actual need but the concept is the same. There is a top level block with many cells within it (level 1). Each block is further subdivided into many more cells (level 2). Those cells are further subdivided into level 3, 4 and 5 for my project but let's just stick to two levels for this question. I'm receiving inputs for my function in the form of "A8, A9, B7, D3". That's a list of cell Ids where each cell Id has the format (level 1 id)(level 2 id). Let's start by comparing just 2 cells, A8 and A9. That's easy because they are in the same block. private static RelativePosition getRelativePositionInTheSameBlock(String v1, String v2) { RelativePosition relativePosition; if( v1-v2 == -1 ) { relativePosition = RelativePosition.LEFT_OF; } else if (v1-v2 == 1) { relativePosition = RelativePosition.RIGHT_OF; } else if (v1-v2 == -BLOCK_WIDTH) { relativePosition = RelativePosition.TOP_OF; } else if (v1-v2 == BLOCK_WIDTH) { relativePosition = RelativePosition.BOTTOM_OF; } else { relativePosition = RelativePosition.NOT_ADJACENT; } return relativePosition; } An A9 - B7 comparison could be done by checking if A is a multiple of BLOCK_WIDTH and whether B is (A-BLOCK_WIDTH+1). Either that or just check naively if the A/B pair is 3-1, 6-4 or 9-7 for better readability. For B7 - D3, they are not adjacent but D3 is adjacent to A9 so I can do a similar adjacency test as above. So getting away from the little details and focusing on the big picture. Is this really the best way to do it? Keeping in mind the following points: I actually have 5 levels not 2, so I could potentially get a list like "A8A1A, A8A1B, B1A2A, B1A2B". Adding a new cell to compare still requires me to compare all the other cells before it (seems like the best I could do for this step is O(n)) The cells aren't all 3x3 blocks, they're just that way for my example. They could be MxN blocks with different M and N for different levels. In my current implementation above, I have separate functions to check adjacency if the cells are in the same blocks, if they are in separate horizontally adjacent blocks or if they are in separate vertically adjacent blocks. That means I have to know the position of the two blocks at the current level before I call one of those functions for the layer below. Judging by the complexity of having to deal with mulitple functions for different edge cases at different levels and having 5 levels of nested if statements. I'm wondering if another design is more suitable. Perhaps a more recursive solution, use of other data structures, or perhaps map the entire multi-level grid to a single-level grid (my quick calculations gives me about 700,000+ atomic cell ids). Even if I go that route, mapping from multi-level to single level is a non-trivial task in itself.

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