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  • nagios check_ping: Invalid hostname/address

    - by lgt
    I'm trying to setup nagios for a host what has the following webroot: www.example.com/ui/html/, but nagios won't accept as host this kind of host path check_ping: Invalid hostname/address. Is there a workaround for this issue? # Define a host for the local machine define host{ use linux-server ; Name of host template to use ; This host definition will inherit all variables that are defined ; in (or inherited by) the linux-server host template definition. host_name example.com/ui/html alias example.com/ui/html address www.example.com/ui/html/ } ############################################################################### ############################################################################### # # SERVICE DEFINITIONS # ############################################################################### ############################################################################### # Define a service to check HTTP on the local machine. # Disable notifications for this service by default, as not all users may have HTTP enabled. define service{ use generic-service name http-service service_description HTTP is_volatile 0 check_period 24x7 max_check_attempts 3 normal_check_interval 5 retry_check_interval 1 notifications_enabled 1 notification_interval 0 notification_period 24x7 notification_options c,r check_command check_http!$HOSTADDRESS$ register 0 } Thanks

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  • URL Parts available to URL Rewrite Rules

    URL Rewrite is a powerful URL rewriting tool available for IIS7 and newer.  Your rewriting options are almost unlimited, giving you the ability to optimize URLs for search engine optimization (SEO), support multiple domain names on a single site, hiding complex paths and much more. URL Rewrite allows you to use any Server Variable as conditions, and with URL Rewrite 2.0, you can also update them on the fly.  To see all variables available to your site, see this post. An understanding...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • URL Multiple Query Parameters Encoded with HTML Entities

    - by BRADINO
    I came across a situation where a URL with multiple query parameters was encoded using htmlentities() and PHP was not recognizing the query parameters using $_GET. A common case for encoding urls using htmlentities() is to use them inside XML documents. So a url with multiple query parameters, encoded using htmlentities() would look like this: http://www.bradino.com/?color=white&amp;size=medium&amp;quantity=3 and when that url is accessed the second and third query parameters are not recognized because instead of separating the subsequent variables with an & that character gets converted into &amp;. I could not find a good way to resolve this, so basically I just encoded the query string back to normal using html_entity_decode() and then slammed the parameters back into the $_GET array using parse_str(). $query = html_entity_decode($_SERVER['QUERY_STRING']); parse_str($query,$_GET); There must be a better way! Anyone come across this before?

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  • Algorithm to make groups of units

    - by M28
    In Age of Mythology and some other strategy games, when you select multiple units and order them to move to some place, they make a "group" when they reach the desired location: I have a Vector with several sprites, which are the selected units, the variables tarX and tarY are the target x and y. I just want an example, so you can just set the x and y position and I can adapt it to my code. Also, I would like to ask that the algorithm calls "isWalkable" for the x and y position, to determine if it's a valid position for each unit.

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  • Performance considerations for common SQL queries

    - by Jim Giercyk
    Originally posted on: http://geekswithblogs.net/NibblesAndBits/archive/2013/10/16/performance-considerations-for-common-sql-queries.aspxSQL offers many different methods to produce the same results.  There is a never-ending debate between SQL developers as to the “best way” or the “most efficient way” to render a result set.  Sometimes these disputes even come to blows….well, I am a lover, not a fighter, so I decided to collect some data that will prove which way is the best and most efficient.  For the queries below, I downloaded the test database from SQLSkills:  http://www.sqlskills.com/sql-server-resources/sql-server-demos/.  There isn’t a lot of data, but enough to prove my point: dbo.member has 10,000 records, and dbo.payment has 15,554.  Our result set contains 6,706 records. The following queries produce an identical result set; the result set contains aggregate payment information for each member who has made more than 1 payment from the dbo.payment table and the first and last name of the member from the dbo.member table.   /*************/ /* Sub Query  */ /*************/ SELECT  a.[Member Number] ,         m.lastname ,         m.firstname ,         a.[Number Of Payments] ,         a.[Average Payment] ,         a.[Total Paid] FROM    ( SELECT    member_no 'Member Number' ,                     AVG(payment_amt) 'Average Payment' ,                     SUM(payment_amt) 'Total Paid' ,                     COUNT(Payment_No) 'Number Of Payments'           FROM      dbo.payment           GROUP BY  member_no           HAVING    COUNT(Payment_No) > 1         ) a         JOIN dbo.member m ON a.[Member Number] = m.member_no         /***************/ /* Cross Apply  */ /***************/ SELECT  ca.[Member Number] ,         m.lastname ,         m.firstname ,         ca.[Number Of Payments] ,         ca.[Average Payment] ,         ca.[Total Paid] FROM    dbo.member m         CROSS APPLY ( SELECT    member_no 'Member Number' ,                                 AVG(payment_amt) 'Average Payment' ,                                 SUM(payment_amt) 'Total Paid' ,                                 COUNT(Payment_No) 'Number Of Payments'                       FROM      dbo.payment                       WHERE     member_no = m.member_no                       GROUP BY  member_no                       HAVING    COUNT(Payment_No) > 1                     ) ca /********/                    /* CTEs  */ /********/ ; WITH    Payments           AS ( SELECT   member_no 'Member Number' ,                         AVG(payment_amt) 'Average Payment' ,                         SUM(payment_amt) 'Total Paid' ,                         COUNT(Payment_No) 'Number Of Payments'                FROM     dbo.payment                GROUP BY member_no                HAVING   COUNT(Payment_No) > 1              ),         MemberInfo           AS ( SELECT   p.[Member Number] ,                         m.lastname ,                         m.firstname ,                         p.[Number Of Payments] ,                         p.[Average Payment] ,                         p.[Total Paid]                FROM     dbo.member m                         JOIN Payments p ON m.member_no = p.[Member Number]              )     SELECT  *     FROM    MemberInfo /************************/ /* SELECT with Grouping   */ /************************/ SELECT  p.member_no 'Member Number' ,         m.lastname ,         m.firstname ,         COUNT(Payment_No) 'Number Of Payments' ,         AVG(payment_amt) 'Average Payment' ,         SUM(payment_amt) 'Total Paid' FROM    dbo.payment p         JOIN dbo.member m ON m.member_no = p.member_no GROUP BY p.member_no ,         m.lastname ,         m.firstname HAVING  COUNT(Payment_No) > 1   We can see what is going on in SQL’s brain by looking at the execution plan.  The Execution Plan will demonstrate which steps and in what order SQL executes those steps, and what percentage of batch time each query takes.  SO….if I execute all 4 of these queries in a single batch, I will get an idea of the relative time SQL takes to execute them, and how it renders the Execution Plan.  We can settle this once and for all.  Here is what SQL did with these queries:   Not only did the queries take the same amount of time to execute, SQL generated the same Execution Plan for each of them.  Everybody is right…..I guess we can all finally go to lunch together!  But wait a second, I may not be a fighter, but I AM an instigator.     Let’s see how a table variable stacks up.  Here is the code I executed: /********************/ /*  Table Variable  */ /********************/ DECLARE @AggregateTable TABLE     (       member_no INT ,       AveragePayment MONEY ,       TotalPaid MONEY ,       NumberOfPayments MONEY     ) INSERT  @AggregateTable         SELECT  member_no 'Member Number' ,                 AVG(payment_amt) 'Average Payment' ,                 SUM(payment_amt) 'Total Paid' ,                 COUNT(Payment_No) 'Number Of Payments'         FROM    dbo.payment         GROUP BY member_no         HAVING  COUNT(Payment_No) > 1   SELECT  at.member_no 'Member Number' ,         m.lastname ,         m.firstname ,         at.NumberOfPayments 'Number Of Payments' ,         at.AveragePayment 'Average Payment' ,         at.TotalPaid 'Total Paid' FROM    @AggregateTable at         JOIN dbo.member m ON m.member_no = at.member_no In the interest of keeping things in groupings of 4, I removed the last query from the previous batch and added the table variable query.  Here’s what I got:     Since we first insert into the table variable, then we read from it, the Execution Plan renders 2 steps.  BUT, the combination of the 2 steps is only 22% of the batch.  It is actually faster than the other methods even though it is treated as 2 separate queries in the Execution Plan.  The argument I often hear against Table Variables is that SQL only estimates 1 row for the table size in the Execution Plan.  While this is true, the estimate does not come in to play until you read from the table variable.  In this case, the table variable had 6,706 rows, but it still outperformed the other queries.  People argue that table variables should only be used for hash or lookup tables.  The fact is, you have control of what you put IN to the variable, so as long as you keep it within reason, these results suggest that a table variable is a viable alternative to sub-queries. If anyone does volume testing on this theory, I would be interested in the results.  My suspicion is that there is a breaking point where efficiency goes down the tubes immediately, and it would be interesting to see where the threshold is. Coding SQL is a matter of style.  If you’ve been around since they introduced DB2, you were probably taught a little differently than a recent computer science graduate.  If you have a company standard, I strongly recommend you follow it.    If you do not have a standard, generally speaking, there is no right or wrong answer when talking about the efficiency of these types of queries, and certainly no hard-and-fast rule.  Volume and infrastructure will dictate a lot when it comes to performance, so your results may vary in your environment.  Download the database and try it!

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  • Error when trying to compile abgx360: C++ compiler cannot create executables

    - by era878
    I am trying to compile the abgx360 GUI. First I run home/eric/Desktop/abgx360-1.0.5/configure but I recieve this error: checking for C++ compiler default output file name... configure: error: C++ compiler cannot create executables See `config.log' for more details. Then i run make but I recieve this error: make: * No rule to make target `/home/eric/Desktop/abgx360-1.0.5/Makefile.am', needed by `/home/eric/Desktop/abgx360-1.0.5/Makefile.in'. Stop. Here is my 'config.log': This file contains any messages produced by compilers while running configure, to aid debugging if configure makes a mistake. It was created by abgx360gui configure 1.0.2, which was generated by GNU Autoconf 2.61. Invocation command line was $ /home/eric/Desktop/abgx360gui-1.0.2/configure ## --------- ## ## Platform. ## ## --------- ## hostname = Eric-Desktop uname -m = x86_64 uname -r = 2.6.35-27-generic uname -s = Linux uname -v = #48-Ubuntu SMP Tue Feb 22 20:25:46 UTC 2011 /usr/bin/uname -p = unknown /bin/uname -X = unknown /bin/arch = unknown /usr/bin/arch -k = unknown /usr/convex/getsysinfo = unknown /usr/bin/hostinfo = unknown /bin/machine = unknown /usr/bin/oslevel = unknown /bin/universe = unknown PATH: /usr/local/sbin PATH: /usr/local/bin PATH: /usr/sbin PATH: /usr/bin PATH: /sbin PATH: /bin PATH: /usr/games ## ----------- ## ## Core tests. ## ## ----------- ## configure:1800: checking for a BSD-compatible install configure:1856: result: /usr/bin/install -c configure:1867: checking whether build environment is sane configure:1910: result: yes configure:1938: checking for a thread-safe mkdir -p configure:1977: result: /bin/mkdir -p configure:1990: checking for gawk configure:2020: result: no configure:1990: checking for mawk configure:2006: found /usr/bin/mawk configure:2017: result: mawk configure:2028: checking whether make sets $(MAKE) configure:2049: result: yes configure:2302: checking for g++ configure:2332: result: no configure:2302: checking for c++ configure:2332: result: no configure:2302: checking for gpp configure:2332: result: no configure:2302: checking for aCC configure:2332: result: no configure:2302: checking for CC configure:2332: result: no configure:2302: checking for cxx configure:2332: result: no configure:2302: checking for cc++ configure:2332: result: no configure:2302: checking for cl.exe configure:2332: result: no configure:2302: checking for FCC configure:2332: result: no configure:2302: checking for KCC configure:2332: result: no configure:2302: checking for RCC configure:2332: result: no configure:2302: checking for xlC_r configure:2332: result: no configure:2302: checking for xlC configure:2332: result: no configure:2360: checking for C++ compiler version configure:2367: g++ --version >&5 /home/eric/Desktop/abgx360gui-1.0.2/configure: line 2368: g++: command not found configure:2370: $? = 127 configure:2377: g++ -v >&5 /home/eric/Desktop/abgx360gui-1.0.2/configure: line 2378: g++: command not found configure:2380: $? = 127 configure:2387: g++ -V >&5 /home/eric/Desktop/abgx360gui-1.0.2/configure: line 2388: g++: command not found configure:2390: $? = 127 configure:2413: checking for C++ compiler default output file name configure:2440: g++ conftest.cpp >&5 /home/eric/Desktop/abgx360gui-1.0.2/configure: line 2441: g++: command not found configure:2443: $? = 127 configure:2481: result: configure: failed program was: | /* confdefs.h. */ | #define PACKAGE_NAME "abgx360gui" | #define PACKAGE_TARNAME "abgx360gui" | #define PACKAGE_VERSION "1.0.2" | #define PACKAGE_STRING "abgx360gui 1.0.2" | #define PACKAGE_BUGREPORT "" | #define PACKAGE "abgx360gui" | #define VERSION "1.0.2" | /* end confdefs.h. */ | | int | main () | { | | ; | return 0; | } configure:2488: error: C++ compiler cannot create executables See `config.log' for more details. ## ---------------- ## ## Cache variables. ## ## ---------------- ## ac_cv_env_CCC_set= ac_cv_env_CCC_value= ac_cv_env_CC_set= ac_cv_env_CC_value= ac_cv_env_CFLAGS_set= ac_cv_env_CFLAGS_value= ac_cv_env_CPPFLAGS_set= ac_cv_env_CPPFLAGS_value= ac_cv_env_CPP_set= ac_cv_env_CPP_value= ac_cv_env_CXXFLAGS_set= ac_cv_env_CXXFLAGS_value= ac_cv_env_CXX_set= ac_cv_env_CXX_value= ac_cv_env_LDFLAGS_set= ac_cv_env_LDFLAGS_value= ac_cv_env_LIBS_set= ac_cv_env_LIBS_value= ac_cv_env_build_alias_set= ac_cv_env_build_alias_value= ac_cv_env_host_alias_set= ac_cv_env_host_alias_value= ac_cv_env_target_alias_set= ac_cv_env_target_alias_value= ac_cv_path_install='/usr/bin/install -c' ac_cv_path_mkdir=/bin/mkdir ac_cv_prog_AWK=mawk ac_cv_prog_make_make_set=yes ## ----------------- ## ## Output variables. ## ## ----------------- ## ACLOCAL='${SHELL} /home/eric/Desktop/abgx360gui-1.0.2/missing --run aclocal-1.10' AMDEPBACKSLASH='' AMDEP_FALSE='' AMDEP_TRUE='' AMTAR='${SHELL} /home/eric/Desktop/abgx360gui-1.0.2/missing --run tar' AUTOCONF='${SHELL} /home/eric/Desktop/abgx360gui-1.0.2/missing --run autoconf' AUTOHEADER='${SHELL} /home/eric/Desktop/abgx360gui-1.0.2/missing --run autoheader' AUTOMAKE='${SHELL} /home/eric/Desktop/abgx360gui-1.0.2/missing --run automake-1.10' AWK='mawk' CC='' CCDEPMODE='' CFLAGS='' CPP='' CPPFLAGS='' CXX='g++' CXXDEPMODE='' CXXFLAGS='' CYGPATH_W='echo' DEFS='' DEPDIR='' ECHO_C='' ECHO_N='-n' ECHO_T='' EGREP='' EXEEXT='' GREP='' INSTALL_DATA='${INSTALL} -m 644' INSTALL_PROGRAM='${INSTALL}' INSTALL_SCRIPT='${INSTALL}' INSTALL_STRIP_PROGRAM='$(install_sh) -c -s' LDFLAGS='' LIBOBJS='' LIBS='' LTLIBOBJS='' MAKEINFO='${SHELL} /home/eric/Desktop/abgx360gui-1.0.2/missing --run makeinfo' OBJEXT='' PACKAGE='abgx360gui' PACKAGE_BUGREPORT='' PACKAGE_NAME='abgx360gui' PACKAGE_STRING='abgx360gui 1.0.2' PACKAGE_TARNAME='abgx360gui' PACKAGE_VERSION='1.0.2' PATH_SEPARATOR=':' SET_MAKE='' SHELL='/bin/bash' STRIP='' VERSION='1.0.2' WX_CFLAGS='' WX_CFLAGS_ONLY='' WX_CONFIG_PATH='' WX_CPPFLAGS='' WX_CXXFLAGS='' WX_CXXFLAGS_ONLY='' WX_LIBS='' WX_LIBS_STATIC='' WX_RESCOMP='' WX_VERSION='' ac_ct_CC='' ac_ct_CXX='' am__fastdepCC_FALSE='' am__fastdepCC_TRUE='' am__fastdepCXX_FALSE='' am__fastdepCXX_TRUE='' am__include='' am__isrc=' -I$(srcdir)' am__leading_dot='.' am__quote='' am__tar='${AMTAR} chof - "$$tardir"' am__untar='${AMTAR} xf -' bindir='${exec_prefix}/bin' build_alias='' datadir='${datarootdir}' datarootdir='${prefix}/share' docdir='${datarootdir}/doc/${PACKAGE_TARNAME}' dvidir='${docdir}' exec_prefix='NONE' host_alias='' htmldir='${docdir}' includedir='${prefix}/include' infodir='${datarootdir}/info' install_sh='$(SHELL) /home/eric/Desktop/abgx360gui-1.0.2/install-sh' libdir='${exec_prefix}/lib' libexecdir='${exec_prefix}/libexec' localedir='${datarootdir}/locale' localstatedir='${prefix}/var' mandir='${datarootdir}/man' mkdir_p='/bin/mkdir -p' oldincludedir='/usr/include' pdfdir='${docdir}' prefix='NONE' program_transform_name='s,x,x,' psdir='${docdir}' sbindir='${exec_prefix}/sbin' sharedstatedir='${prefix}/com' sysconfdir='${prefix}/etc' target_alias='' ## ----------- ## ## confdefs.h. ## ## ----------- ## #define PACKAGE_NAME "abgx360gui" #define PACKAGE_TARNAME "abgx360gui" #define PACKAGE_VERSION "1.0.2" #define PACKAGE_STRING "abgx360gui 1.0.2" #define PACKAGE_BUGREPORT "" #define PACKAGE "abgx360gui" #define VERSION "1.0.2" configure: exit 77

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  • NET Math Libraries

    - by JoshReuben
    NET Mathematical Libraries   .NET Builder for Matlab The MathWorks Inc. - http://www.mathworks.com/products/netbuilder/ MATLAB Builder NE generates MATLAB based .NET and COM components royalty-free deployment creates the components by encrypting MATLAB functions and generating either a .NET or COM wrapper around them. .NET/Link for Mathematica www.wolfram.com a product that 2-way integrates Mathematica and Microsoft's .NET platform call .NET from Mathematica - use arbitrary .NET types directly from the Mathematica language. use and control the Mathematica kernel from a .NET program. turns Mathematica into a scripting shell to leverage the computational services of Mathematica. write custom front ends for Mathematica or use Mathematica as a computational engine for another program comes with full source code. Leverages MathLink - a Wolfram Research's protocol for sending data and commands back and forth between Mathematica and other programs. .NET/Link abstracts the low-level details of the MathLink C API. Extreme Optimization http://www.extremeoptimization.com/ a collection of general-purpose mathematical and statistical classes built for the.NET framework. It combines a math library, a vector and matrix library, and a statistics library in one package. download the trial of version 4.0 to try it out. Multi-core ready - Full support for Task Parallel Library features including cancellation. Broad base of algorithms covering a wide range of numerical techniques, including: linear algebra (BLAS and LAPACK routines), numerical analysis (integration and differentiation), equation solvers. Mathematics leverages parallelism using .NET 4.0's Task Parallel Library. Basic math: Complex numbers, 'special functions' like Gamma and Bessel functions, numerical differentiation. Solving equations: Solve equations in one variable, or solve systems of linear or nonlinear equations. Curve fitting: Linear and nonlinear curve fitting, cubic splines, polynomials, orthogonal polynomials. Optimization: find the minimum or maximum of a function in one or more variables, linear programming and mixed integer programming. Numerical integration: Compute integrals over finite or infinite intervals, over 2D and higher dimensional regions. Integrate systems of ordinary differential equations (ODE's). Fast Fourier Transforms: 1D and 2D FFT's using managed or fast native code (32 and 64 bit) BigInteger, BigRational, and BigFloat: Perform operations with arbitrary precision. Vector and Matrix Library Real and complex vectors and matrices. Single and double precision for elements. Structured matrix types: including triangular, symmetrical and band matrices. Sparse matrices. Matrix factorizations: LU decomposition, QR decomposition, singular value decomposition, Cholesky decomposition, eigenvalue decomposition. Portability and performance: Calculations can be done in 100% managed code, or in hand-optimized processor-specific native code (32 and 64 bit). Statistics Data manipulation: Sort and filter data, process missing values, remove outliers, etc. Supports .NET data binding. Statistical Models: Simple, multiple, nonlinear, logistic, Poisson regression. Generalized Linear Models. One and two-way ANOVA. Hypothesis Tests: 12 14 hypothesis tests, including the z-test, t-test, F-test, runs test, and more advanced tests, such as the Anderson-Darling test for normality, one and two-sample Kolmogorov-Smirnov test, and Levene's test for homogeneity of variances. Multivariate Statistics: K-means cluster analysis, hierarchical cluster analysis, principal component analysis (PCA), multivariate probability distributions. Statistical Distributions: 25 29 continuous and discrete statistical distributions, including uniform, Poisson, normal, lognormal, Weibull and Gumbel (extreme value) distributions. Random numbers: Random variates from any distribution, 4 high-quality random number generators, low discrepancy sequences, shufflers. New in version 4.0 (November, 2010) Support for .NET Framework Version 4.0 and Visual Studio 2010 TPL Parallellized – multicore ready sparse linear program solver - can solve problems with more than 1 million variables. Mixed integer linear programming using a branch and bound algorithm. special functions: hypergeometric, Riemann zeta, elliptic integrals, Frensel functions, Dawson's integral. Full set of window functions for FFT's. Product  Price Update subscription Single Developer License $999  $399  Team License (3 developers) $1999  $799  Department License (8 developers) $3999  $1599  Site License (Unlimited developers in one physical location) $7999  $3199    NMath http://www.centerspace.net .NET math and statistics libraries matrix and vector classes random number generators Fast Fourier Transforms (FFTs) numerical integration linear programming linear regression curve and surface fitting optimization hypothesis tests analysis of variance (ANOVA) probability distributions principal component analysis cluster analysis built on the Intel Math Kernel Library (MKL), which contains highly-optimized, extensively-threaded versions of BLAS (Basic Linear Algebra Subroutines) and LAPACK (Linear Algebra PACKage). Product  Price Update subscription Single Developer License $1295 $388 Team License (5 developers) $5180 $1554   DotNumerics http://www.dotnumerics.com/NumericalLibraries/Default.aspx free DotNumerics is a website dedicated to numerical computing for .NET that includes a C# Numerical Library for .NET containing algorithms for Linear Algebra, Differential Equations and Optimization problems. The Linear Algebra library includes CSLapack, CSBlas and CSEispack, ports from Fortran to C# of LAPACK, BLAS and EISPACK, respectively. Linear Algebra (CSLapack, CSBlas and CSEispack). Systems of linear equations, eigenvalue problems, least-squares solutions of linear systems and singular value problems. Differential Equations. Initial-value problem for nonstiff and stiff ordinary differential equations ODEs (explicit Runge-Kutta, implicit Runge-Kutta, Gear's BDF and Adams-Moulton). Optimization. Unconstrained and bounded constrained optimization of multivariate functions (L-BFGS-B, Truncated Newton and Simplex methods).   Math.NET Numerics http://numerics.mathdotnet.com/ free an open source numerical library - includes special functions, linear algebra, probability models, random numbers, interpolation, integral transforms. A merger of dnAnalytics with Math.NET Iridium in addition to a purely managed implementation will also support native hardware optimization. constants & special functions complex type support real and complex, dense and sparse linear algebra (with LU, QR, eigenvalues, ... decompositions) non-uniform probability distributions, multivariate distributions, sample generation alternative uniform random number generators descriptive statistics, including order statistics various interpolation methods, including barycentric approaches and splines numerical function integration (quadrature) routines integral transforms, like fourier transform (FFT) with arbitrary lengths support, and hartley spectral-space aware sequence manipulation (signal processing) combinatorics, polynomials, quaternions, basic number theory. parallelized where appropriate, to leverage multi-core and multi-processor systems fully managed or (if available) using native libraries (Intel MKL, ACMS, CUDA, FFTW) provides a native facade for F# developers

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  • ODI 11g - Oracle Data Integrator 11g – A Hands-On Tutorial

    - by David Allan
    I've have been asked by Packt publishing to review a brand new book on Oracle Data Integrator: Getting Started with Oracle Data Integrator 11g – A Hands-On Tutorial. Waiting on this book to arrive and see what goodies are inside, I'll blog a review later. The book can be found at Oracle Data Integrator 11g – A Hands-On Tutorial Looking at the table of contents, it looks like it gives a good broad introduction (including various data formats) to the product; Chapter 1: Product Overview Chapter 2: Product Installation Chapter 3: Using Variables Chapter 4: ODI Sources, Targets, and Knowledge Modules Chapter 5: Working with Databases Chapter 6: Working with MySQL Chapter 7: Working with Microsoft SQL Server Chapter 8: Integrating File Data Chapter 9: Working with XML Files Chapter 10: Creating Workflows—Packages and Load Plans Chapter 11: Error Management Chapter 12: Managing and Monitoring ODI Components Chapter 13: Concluding Remarks Looking forward to it.

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  • can't load big files to server with php [closed]

    - by yozhik
    Hi all! I can't load big files to server. The problem is in that file $_FILES["filename"]["tmp_name"] is empty if file a little more bigger then 2mb. I tried to change variables in php.ini upload_max_filesize = 700M post_max_size = 16M but not working to. Also tried to add this variables to my .httaccess file - but 500 error appears. Error code while uploading=1. UPLOAD_ERR_INI_SIZE Value: 1; The uploaded file exceeds the upload_max_filesize directive in php.ini. Here is my uppload.php page, please anwer what I doing wrong? Thanx! <?php if(strlen($_FILES["filename"]["name"])) { $folder = "uploads/"; echo $folder; $error = ""; if($_FILES["filename"]["size"] > 1024*700*1024) { $error .= "<b><p class=ErrorMessage>?????? ????? ????????? 5Mb</p></b><br>"; header("Location: upload.php?error=".$error, true, 303 ); } if(!file_exists($folder.="hh/")) { if(!mkdir($folder, 0700)) $error .= "<b><p class=ErrorMessage>Folder not created</p></b><br>"; } //echo "<br>".$_FILES["filename"]["tmp_name"]."<br>"; echo $folder.$_FILES["filename"]["name"]."<br>"; echo $_FILES["filename"]["error"]."<br>"; if(move_uploaded_file($_FILES["filename"]["tmp_name"], $folder.$_FILES["filename"]["name"])) { echo("???? ??????? ???????? <br>"); echo("?????????????? ?????: <br>"); echo("??? ?????: "); echo($_FILES["filename"]["name"]); echo("<br>?????? ?????: "); echo($_FILES["filename"]["size"]); echo("<br>??????? ??? ????????: "); echo($folder.=$_FILES["filename"]["name"]); echo("<br>??? ?????: "); echo($_FILES["filename"]["type"]); } else { $error .= "<b><p class=ErrorMessage>?????? ???????? ?????</p></b><br>"; } } ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>???????? ??? ????????</title> </head> <body> <?php if(isset($_REQUEST["error"])) { echo $_REQUEST["error"]; } ?> <h2><p><b> ????? ??? ???????? ?????? </b></p></h2> <form action="upload.php" method="post" enctype="multipart/form-data"> <input type="file" name="filename" READONLY><br> <input name="Upload" type="submit" value="Upload"><br> </form> </body> </html>

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  • The purpose of using a constants pool for immutable constants

    - by patstuart
    Originally posted at stackoverflow.com/q/23961260 I come across the following code with a lot of frequency: if (myArray.length == Constants.ZERO_INT) or if (myString != null && !myString.equals(Constants.EMPTY_STRING)) Neither of these makes much sense to me. Isn't the point of having a constant pool for ease of code appearance and to allow for modularity? In both of the above cases, it just looks like needless noise that accomplishes neither objective. My question: what is the purpose of using a constants pool for variables like this which will never change? Or is this just cargo cult programming? If so, then why does it seem to be prevalent in the industry? (I've noticed it with at least two different employers I've worked with).

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  • Codeigniter PHP Framework - Need to get query string

    - by Siva
    Hi, I'm creating a e-commerce site using Codeigniter. My question is, how should i get the query string. Am using a saferpay payment gateway, the gateway response will be like this http://www.test.com/registration/success/?DATA=<IDP+MSGTYPE%3D"PayConfirm"+KEYID%3D"1-0"+ID%3D"KI2WSWAn5UG3vAQv80AdAbpplvnb"+TOKEN%3D"(unused)"+VTVERIFY%3D"(obsolete)"+IP%3D" 123.25.37.43"+IPCOUNTRY%3D"IN"+AMOUNT%3D"832200"+CURRENCY%3D"CHF"+PROVIDERID%3D"90"+PROVIDERNAME%3D"Saferpay+Test+Card"+ACCOUNTID%3D"99867-94913159"+ECI%3D"2"+CCCOUNTRY%3D"XX"%2F>&SIGNATURE=bc8e253e2a8c9ee0271fc45daca05eecc43139be6e7d486f0d6f68a356865457a3afad86102a4d49cf2f6a33a8fc6513812e9bff23371432feace0580f55046c To handle the response i need to get the query string data. Help would be much appreciated. Thanks in advance. - Siva

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  • MYSQL – Identifying Current Version of MySQL Server Installation – Part 2

    - by Pinal Dave
    Earlier I wrote an article about Detecting Current Version of MySQL Server Installation. After the post quite a few emails I received where various users suggested that there are many more ways to figure out the version of MySQL. Here are few of the methods which I received in the email. Method 1: This method retrieves value with the help of Information Functions. SELECT VERSION(); Method 2: This method is very similar to SQL Server. SELECT @@Version Method 3: You can connect to MySQL with command prompt and type following command: STATUS; Method 4: Please refer my earlier blog post. SHOW VARIABLES LIKE "%version%"; Let me know if you know any more method and I will extend this blog post. Reference : Pinal Dave (http://blog.SQLAuthority.com)Filed under: MySQL, PostADay, SQL, SQL Authority, SQL Query, SQL Tips and Tricks, T SQL

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  • Date and Time Support in SQL Server 2008

    - by Aamir Hasan
      Using the New Date and Time Data Types Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} 1.       The new date and time data types in SQL Server 2008 offer increased range and precision and are ANSI SQL compatible. 2.       Separate date and time data types minimize storage space requirements for applications that need only date or time information. Moreover, the variable precision of the new time data type increases storage savings in exchange for reduced accuracy. 3.       The new data types are mostly compatible with the original date and time data types and use the same Transact-SQL functions. 4.       The datetimeoffset data type allows you to handle date and time information in global applications that use data that originates from different time zones. SELECT c.name, p.* FROM politics pJOIN country cON p.country = c.codeWHERE YEAR(Independence) < 1753ORDER BY IndependenceGO8.    Highlight the SELECT statement and click Execute ( ) to show the use of some of the date functions.T-SQLSELECT c.name AS [Country Name],        CONVERT(VARCHAR(12), p.Independence, 107) AS [Independence Date],       DATEDIFF(YEAR, p.Independence, GETDATE()) AS [Years Independent (appox)],       p.GovernmentFROM politics pJOIN country cON p.country = c.codeWHERE YEAR(Independence) < 1753ORDER BY IndependenceGO10.    Select the SET DATEFORMAT statement and click Execute ( ) to change the DATEFORMAT to day-month-year.T-SQLSET DATEFORMAT dmyGO11.    Select the DECLARE and SELECT statements and click Execute ( ) to show how the datetime and datetime2 data types interpret a date literal.T-SQLSET DATEFORMAT dmyDECLARE @dt datetime = '2008-12-05'DECLARE @dt2 datetime2 = '2008-12-05'SELECT MONTH(@dt) AS [Month-Datetime], DAY(@dt)     AS [Day-Datetime]SELECT MONTH(@dt2) AS [Month-Datetime2], DAY(@dt2)     AS [Day-Datetime2]GO12.    Highlight the DECLARE and SELECT statements and click Execute ( ) to use integer arithmetic on a datetime variable.T-SQLDECLARE @dt datetime = '2008-12-05'SELECT @dt + 1GO13.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how integer arithmetic is not allowed for datetime2 variables.T-SQLDECLARE @dt2 datetime = '2008-12-05'SELECT @dt2 + 1GO14.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how to use DATE functions to do simple arithmetic on datetime2 variables.T-SQLDECLARE @dt2 datetime2(7) = '2008-12-05'SELECT DATEADD(d, 1, @dt2)GO15.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how the GETDATE function can be used with both datetime and datetime2 data types.T-SQLDECLARE @dt datetime = GETDATE();DECLARE @dt2 datetime2(7) = GETDATE();SELECT @dt AS [GetDate-DateTime], @dt2 AS [GetDate-DateTime2]GO16.    Draw attention to the values returned for both columns and how they are equal.17.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how the SYSDATETIME function can be used with both datetime and datetime2 data types.T-SQLDECLARE @dt datetime = SYSDATETIME();DECLARE @dt2 datetime2(7) = SYSDATETIME();SELECT @dt AS [Sysdatetime-DateTime], @dt2     AS [Sysdatetime-DateTime2]GO18.    Draw attention to the values returned for both columns and how they are different.Programming Global Applications with DateTimeOffset 2.    If you have not previously created the SQLTrainingKitDB database while completing another demo in this training kit, highlight the CREATE DATABASE statement and click Execute ( ) to do so now.T-SQLCREATE DATABASE SQLTrainingKitDBGO3.    Select the USE and CREATE TABLE statements and click Execute ( ) to create table datetest in the SQLTrainingKitDB database.T-SQLUSE SQLTrainingKitDBGOCREATE TABLE datetest (  id integer IDENTITY PRIMARY KEY,  datetimecol datetimeoffset,  EnteredTZ varchar(40)); Reference:http://www.microsoft.com/downloads/details.aspx?FamilyID=E9C68E1B-1E0E-4299-B498-6AB3CA72A6D7&displaylang=en   

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  • CSS Redundancy checker for GWT

    - by cupakob
    In my project i have a lot of css styles. Some of them are never used (not anymore). I check this manually with eclipse: i select text and then with "Search - Text - Project" i can find, if this style occurs only in the stylesheet or also in java files. Is there better way to check, which styles are currently used in my GWT project? edit: @Igor,Keith: thanks for the hint, but i'm not using the CssResource to insert my css file. Instead i use my index.html. And i want to remove the unused styles just for better overview. CssResource is not exactly, what i'm looking for.

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  • Determining if you&rsquo;re running on the build server with MSBuild &ndash; Easy way

    - by ParadigmShift
    When you're customizing MSBuild in building a visual studio project, it often becomes important to determine if the build is running on the build server or your development environment. This information can change the way you set up path variables and other Conditional tasks.I've found many different answers online. It seems like they all only worked under certain conditions, so none of them were guaranteed to be consistent.So here's the simplest way I've found that has not failed me yet. <PropertyGroup> <!-- Determine if the current build is running on the build server --> <IsBuildServer>false</IsBuildServer> <IsBuildServer Condition="'$(BuildUri)' != ''">true</IsBuildServer> </PropertyGroup>   Shahzad Qureshi is a Software Engineer and Consultant in Salt Lake City, Utah, USAHis certifications include:Microsoft Certified System Engineer 3CX Certified Partner Global Information Assurance Certification – Secure Software Programmer – .NETHe is the owner of Utah VoIP Store at www.UtahVoIPStore.com and SWS Development at www.swsdev.com and publishes windows apps under the name Blue Voice.

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  • Ant Colony Optimization de Marco Dorigo et Thomas Stützle, critique par Franck Dernoncourt

    Bonjour à tous, Voici ma critique du livre "Ant Colony Optimization". Les algorithmes de colonies de fourmis sont des algorithmes inspirés du comportement des fourmis et qui constituent une famille de métaheuristiques d'optimisation. Ils ont été appliqués à un grand nombre de problèmes d'optimisation combinatoire, allant de l'assignement quadratique au replis de protéine ou au routage de véhicules. Comme beaucoup de métaheuristiques, l'algorithme de base a été adapté aux problèmes dynamiques, en variables réelles, aux problèmes stochastiques, multi-objectifs ou aux implémentations parallèles, etc. Bref, c'est une métaheuristique incontournable pour toute pe...

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  • EJB3 Business Delegates

    - by mykola
    Is there any reason for making delegate when using EJB3? Because the only real benefit i see from delegate is that it allows to hide lookup and access details of EJB architecture. Well it also provides some decoupling but it's mostly unused, imho. With EJB3 we have injection so now i can just create a variable with @EJB annotation and use it as is. Do i still need delegates? Is this injection resource consuming? I mean if i use it in JSF's request managed beans may be it's still better to use delegates just to lessen these injection calls? Thank you!

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  • Atmospheric Scattering

    - by Lawrence Kok
    I'm trying to implement atmospheric scattering based on Sean O`Neil algorithm that was published in GPU Gems 2. But I have some trouble getting the shader to work. My latest attempts resulted in: http://img253.imageshack.us/g/scattering01.png/ I've downloaded sample code of O`Neil from: http://http.download.nvidia.com/developer/GPU_Gems_2/CD/Index.html. Made minor adjustments to the shader 'SkyFromAtmosphere' that would allow it to run in AMD RenderMonkey. In the images it is see-able a form of banding occurs, getting an blueish tone. However it is only applied to one half of the sphere, the other half is completely black. Also the banding appears to occur at Zenith instead of Horizon, and for a reason I managed to get pac-man shape. I would appreciate it if somebody could show me what I'm doing wrong. Vertex Shader: uniform mat4 matView; uniform vec4 view_position; uniform vec3 v3LightPos; const int nSamples = 3; const float fSamples = 3.0; const vec3 Wavelength = vec3(0.650,0.570,0.475); const vec3 v3InvWavelength = 1.0f / vec3( Wavelength.x * Wavelength.x * Wavelength.x * Wavelength.x, Wavelength.y * Wavelength.y * Wavelength.y * Wavelength.y, Wavelength.z * Wavelength.z * Wavelength.z * Wavelength.z); const float fInnerRadius = 10; const float fOuterRadius = fInnerRadius * 1.025; const float fInnerRadius2 = fInnerRadius * fInnerRadius; const float fOuterRadius2 = fOuterRadius * fOuterRadius; const float fScale = 1.0 / (fOuterRadius - fInnerRadius); const float fScaleDepth = 0.25; const float fScaleOverScaleDepth = fScale / fScaleDepth; const vec3 v3CameraPos = vec3(0.0, fInnerRadius * 1.015, 0.0); const float fCameraHeight = length(v3CameraPos); const float fCameraHeight2 = fCameraHeight * fCameraHeight; const float fm_ESun = 150.0; const float fm_Kr = 0.0025; const float fm_Km = 0.0010; const float fKrESun = fm_Kr * fm_ESun; const float fKmESun = fm_Km * fm_ESun; const float fKr4PI = fm_Kr * 4 * 3.141592653; const float fKm4PI = fm_Km * 4 * 3.141592653; varying vec3 v3Direction; varying vec4 c0, c1; float scale(float fCos) { float x = 1.0 - fCos; return fScaleDepth * exp(-0.00287 + x*(0.459 + x*(3.83 + x*(-6.80 + x*5.25)))); } void main( void ) { // Get the ray from the camera to the vertex, and its length (which is the far point of the ray passing through the atmosphere) vec3 v3FrontColor = vec3(0.0, 0.0, 0.0); vec3 v3Pos = normalize(gl_Vertex.xyz) * fOuterRadius; vec3 v3Ray = v3CameraPos - v3Pos; float fFar = length(v3Ray); v3Ray = normalize(v3Ray); // Calculate the ray's starting position, then calculate its scattering offset vec3 v3Start = v3CameraPos; float fHeight = length(v3Start); float fDepth = exp(fScaleOverScaleDepth * (fInnerRadius - fCameraHeight)); float fStartAngle = dot(v3Ray, v3Start) / fHeight; float fStartOffset = fDepth*scale(fStartAngle); // Initialize the scattering loop variables float fSampleLength = fFar / fSamples; float fScaledLength = fSampleLength * fScale; vec3 v3SampleRay = v3Ray * fSampleLength; vec3 v3SamplePoint = v3Start + v3SampleRay * 0.5; // Now loop through the sample rays for(int i=0; i<nSamples; i++) { float fHeight = length(v3SamplePoint); float fDepth = exp(fScaleOverScaleDepth * (fInnerRadius - fHeight)); float fLightAngle = dot(normalize(v3LightPos), v3SamplePoint) / fHeight; float fCameraAngle = dot(normalize(v3Ray), v3SamplePoint) / fHeight; float fScatter = (-fStartOffset + fDepth*( scale(fLightAngle) - scale(fCameraAngle)))/* 0.25f*/; vec3 v3Attenuate = exp(-fScatter * (v3InvWavelength * fKr4PI + fKm4PI)); v3FrontColor += v3Attenuate * (fDepth * fScaledLength); v3SamplePoint += v3SampleRay; } // Finally, scale the Mie and Rayleigh colors and set up the varying variables for the pixel shader vec4 newPos = vec4( (gl_Vertex.xyz + view_position.xyz), 1.0); gl_Position = gl_ModelViewProjectionMatrix * vec4(newPos.xyz, 1.0); gl_Position.z = gl_Position.w * 0.99999; c1 = vec4(v3FrontColor * fKmESun, 1.0); c0 = vec4(v3FrontColor * (v3InvWavelength * fKrESun), 1.0); v3Direction = v3CameraPos - v3Pos; } Fragment Shader: uniform vec3 v3LightPos; varying vec3 v3Direction; varying vec4 c0; varying vec4 c1; const float g =-0.90f; const float g2 = g * g; const float Exposure =2; void main(void){ float fCos = dot(normalize(v3LightPos), v3Direction) / length(v3Direction); float fMiePhase = 1.5 * ((1.0 - g2) / (2.0 + g2)) * (1.0 + fCos*fCos) / pow(1.0 + g2 - 2.0*g*fCos, 1.5); gl_FragColor = c0 + fMiePhase * c1; gl_FragColor.a = 1.0; }

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  • Java default Integer value is int

    - by Chris Okyen
    My code looks like this import java.util.Scanner; public class StudentGrades { public static void main(String[] argv) { Scanner keyboard = new Scanner(System.in); byte q1 = keyboard.nextByte() * 10; } } It gives me an error "Type mismatch: cannot convert from int to byte." Why the heck would Java store a literal operand that is small enough to fit in a byte,. into a int type? Do literals get stored in variables/registers before the ALU performs arithmatic operations.

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  • Raycasting tutorial / vector math question

    - by mattboy
    I'm checking out this nice raycasting tutorial at http://lodev.org/cgtutor/raycasting.html and have a probably very simple math question. In the DDA algorithm I'm having trouble understanding the calcuation of the deltaDistX and deltaDistY variables, which are the distances that the ray has to travel from 1 x-side to the next x-side, or from 1 y-side to the next y-side, in the square grid that makes up the world map (see below screenshot). In the tutorial they are calculated as follows, but without much explanation: //length of ray from one x or y-side to next x or y-side double deltaDistX = sqrt(1 + (rayDirY * rayDirY) / (rayDirX * rayDirX)); double deltaDistY = sqrt(1 + (rayDirX * rayDirX) / (rayDirY * rayDirY)); rayDirY and rayDirX are the direction of a ray that has been cast. How do you get these formulas? It looks like pythagorean theorem is part of it, but somehow there's division involved here. Can anyone clue me in as to what mathematical knowledge I'm missing here, or "prove" the formula by showing how it's derived?

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  • Linq to SQl over WCF Timesout after several calls

    - by Redeemed1
    I have a L2S Repository class which instantiates the L2S DataContext in its constructor. The repository is instantiated at run time (using Unity) in a service hosted in IIS with WCF. When I run up the client MVC applicaton the calls to the backend WCF service work for a while and then timeout. I suspected perhaps a database issue as I was depending on IIS garbage collection to dispose of unused DataContext instances in the IIS host but when I checked the characteristics of the problem I notice the following: The client makes the call to WCF but the WCF service does not respond. Next, the client times out Some time later (several minutes) the service actually executes the request by instantiating the repository and servicing the call. I have checked both client and server traces logs and only the client shows WCF errors (the timeout error). Where should I look? Is it something in WCF or is L2S possibly blocking with unfreed conenctions, resources etc.? Many thanks Brian

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  • Using IP Restrictions with URL Rewrite-Week 25

    - by OWScott
    URL Rewrite offers tremendous flexibility for customizing rules to your environment. One area of functionality that is often desired for URL Rewrite is to allow a large list of approved or denied IP addresses and subnet ranges. IIS’s original IP Restrictions is helpful for fully blocking an IP address, but it doesn’t offer the flexibility that URL Rewrite does. An example where URL Rewrite is helpful is where you want to allow only authorized IPs to access staging.yoursite.com, but where staging.yoursite.com is part of the same site as www.yoursite.com. This requires conditional logic for the user’s IP. This lesson covers this unique situation while also introducing Rewrite Maps, server variables, and pairing rules to add more flexibility. This is week 25 of a 52 week series for the Web Pro. Past and future videos can be found here: http://dotnetslackers.com/projects/LearnIIS7/ You can find this week’s video here.

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  • Internationalization of non-english application

    - by Jacket
    I know there are lots of posts for internationalization, but this is something I didn't found while searching. I have a PHP Web application, which is pretty big right now. It's developed actively for 4 years and wasn't built with internationalization in mind. Text is everywhere - in plain HTML, in PHP variables, in echo's, in the DB... Now I'm familiar with the concept of gettext and this is what i plan to use for the internationalization project of the application. However the app is not written in English and here is my question: Should I first translate everything to English while wrapping every string in gettext() function, or I can use my native language as a base? P.S. also any quick suggestions (links maybe) on making my life easier with the whole i18n project will be greatly appreciated!

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  • Using Stub Objects

    - by user9154181
    Having told the long and winding tale of where stub objects came from and how we use them to build Solaris, I'd like to focus now on the the nuts and bolts of building and using them. The following new features were added to the Solaris link-editor (ld) to support the production and use of stub objects: -z stub This new command line option informs ld that it is to build a stub object rather than a normal object. In this mode, it accepts the same command line arguments as usual, but will quietly ignore any objects and sharable object dependencies. STUB_OBJECT Mapfile Directive In order to build a stub version of an object, its mapfile must specify the STUB_OBJECT directive. When producing a non-stub object, the presence of STUB_OBJECT causes the link-editor to perform extra validation to ensure that the stub and non-stub objects will be compatible. ASSERT Mapfile Directive All data symbols exported from the object must have an ASSERT symbol directive in the mapfile that declares them as data and supplies the size, binding, bss attributes, and symbol aliasing details. When building the stub objects, the information in these ASSERT directives is used to create the data symbols. When building the real object, these ASSERT directives will ensure that the real object matches the linking interface presented by the stub. Although ASSERT was added to the link-editor in order to support stub objects, they are a general purpose feature that can be used independently of stub objects. For instance you might choose to use an ASSERT directive if you have a symbol that must have a specific address in order for the object to operate properly and you want to automatically ensure that this will always be the case. The material presented here is derived from a document I originally wrote during the development effort, which had the dual goals of providing supplemental materials for the stub object PSARC case, and as a set of edits that were eventually applied to the Oracle Solaris Linker and Libraries Manual (LLM). The Solaris 11 LLM contains this information in a more polished form. Stub Objects A stub object is a shared object, built entirely from mapfiles, that supplies the same linking interface as the real object, while containing no code or data. Stub objects cannot be used at runtime. However, an application can be built against a stub object, where the stub object provides the real object name to be used at runtime, and then use the real object at runtime. When building a stub object, the link-editor ignores any object or library files specified on the command line, and these files need not exist in order to build a stub. Since the compilation step can be omitted, and because the link-editor has relatively little work to do, stub objects can be built very quickly. Stub objects can be used to solve a variety of build problems: Speed Modern machines, using a version of make with the ability to parallelize operations, are capable of compiling and linking many objects simultaneously, and doing so offers significant speedups. However, it is typical that a given object will depend on other objects, and that there will be a core set of objects that nearly everything else depends on. It is necessary to impose an ordering that builds each object before any other object that requires it. This ordering creates bottlenecks that reduce the amount of parallelization that is possible and limits the overall speed at which the code can be built. Complexity/Correctness In a large body of code, there can be a large number of dependencies between the various objects. The makefiles or other build descriptions for these objects can become very complex and difficult to understand or maintain. The dependencies can change as the system evolves. This can cause a given set of makefiles to become slightly incorrect over time, leading to race conditions and mysterious rare build failures. Dependency Cycles It might be desirable to organize code as cooperating shared objects, each of which draw on the resources provided by the other. Such cycles cannot be supported in an environment where objects must be built before the objects that use them, even though the runtime linker is fully capable of loading and using such objects if they could be built. Stub shared objects offer an alternative method for building code that sidesteps the above issues. Stub objects can be quickly built for all the shared objects produced by the build. Then, all the real shared objects and executables can be built in parallel, in any order, using the stub objects to stand in for the real objects at link-time. Afterwards, the executables and real shared objects are kept, and the stub shared objects are discarded. Stub objects are built from a mapfile, which must satisfy the following requirements. The mapfile must specify the STUB_OBJECT directive. This directive informs the link-editor that the object can be built as a stub object, and as such causes the link-editor to perform validation and sanity checking intended to guarantee that an object and its stub will always provide identical linking interfaces. All function and data symbols that make up the external interface to the object must be explicitly listed in the mapfile. The mapfile must use symbol scope reduction ('*'), to remove any symbols not explicitly listed from the external interface. All global data exported from the object must have an ASSERT symbol attribute in the mapfile to specify the symbol type, size, and bss attributes. In the case where there are multiple symbols that reference the same data, the ASSERT for one of these symbols must specify the TYPE and SIZE attributes, while the others must use the ALIAS attribute to reference this primary symbol. Given such a mapfile, the stub and real versions of the shared object can be built using the same command line for each, adding the '-z stub' option to the link for the stub object, and omiting the option from the link for the real object. To demonstrate these ideas, the following code implements a shared object named idx5, which exports data from a 5 element array of integers, with each element initialized to contain its zero-based array index. This data is available as a global array, via an alternative alias data symbol with weak binding, and via a functional interface. % cat idx5.c int _idx5[5] = { 0, 1, 2, 3, 4 }; #pragma weak idx5 = _idx5 int idx5_func(int index) { if ((index 4)) return (-1); return (_idx5[index]); } A mapfile is required to describe the interface provided by this shared object. % cat mapfile $mapfile_version 2 STUB_OBJECT; SYMBOL_SCOPE { _idx5 { ASSERT { TYPE=data; SIZE=4[5] }; }; idx5 { ASSERT { BINDING=weak; ALIAS=_idx5 }; }; idx5_func; local: *; }; The following main program is used to print all the index values available from the idx5 shared object. % cat main.c #include <stdio.h> extern int _idx5[5], idx5[5], idx5_func(int); int main(int argc, char **argv) { int i; for (i = 0; i The following commands create a stub version of this shared object in a subdirectory named stublib. elfdump is used to verify that the resulting object is a stub. The command used to build the stub differs from that of the real object only in the addition of the -z stub option, and the use of a different output file name. This demonstrates the ease with which stub generation can be added to an existing makefile. % cc -Kpic -G -M mapfile -h libidx5.so.1 idx5.c -o stublib/libidx5.so.1 -zstub % ln -s libidx5.so.1 stublib/libidx5.so % elfdump -d stublib/libidx5.so | grep STUB [11] FLAGS_1 0x4000000 [ STUB ] The main program can now be built, using the stub object to stand in for the real shared object, and setting a runpath that will find the real object at runtime. However, as we have not yet built the real object, this program cannot yet be run. Attempts to cause the system to load the stub object are rejected, as the runtime linker knows that stub objects lack the actual code and data found in the real object, and cannot execute. % cc main.c -L stublib -R '$ORIGIN/lib' -lidx5 -lc % ./a.out ld.so.1: a.out: fatal: libidx5.so.1: open failed: No such file or directory Killed % LD_PRELOAD=stublib/libidx5.so.1 ./a.out ld.so.1: a.out: fatal: stublib/libidx5.so.1: stub shared object cannot be used at runtime Killed We build the real object using the same command as we used to build the stub, omitting the -z stub option, and writing the results to a different file. % cc -Kpic -G -M mapfile -h libidx5.so.1 idx5.c -o lib/libidx5.so.1 Once the real object has been built in the lib subdirectory, the program can be run. % ./a.out [0] 0 0 0 [1] 1 1 1 [2] 2 2 2 [3] 3 3 3 [4] 4 4 4 Mapfile Changes The version 2 mapfile syntax was extended in a number of places to accommodate stub objects. Conditional Input The version 2 mapfile syntax has the ability conditionalize mapfile input using the $if control directive. As you might imagine, these directives are used frequently with ASSERT directives for data, because a given data symbol will frequently have a different size in 32 or 64-bit code, or on differing hardware such as x86 versus sparc. The link-editor maintains an internal table of names that can be used in the logical expressions evaluated by $if and $elif. At startup, this table is initialized with items that describe the class of object (_ELF32 or _ELF64) and the type of the target machine (_sparc or _x86). We found that there were a small number of cases in the Solaris code base in which we needed to know what kind of object we were producing, so we added the following new predefined items in order to address that need: NameMeaning ...... _ET_DYNshared object _ET_EXECexecutable object _ET_RELrelocatable object ...... STUB_OBJECT Directive The new STUB_OBJECT directive informs the link-editor that the object described by the mapfile can be built as a stub object. STUB_OBJECT; A stub shared object is built entirely from the information in the mapfiles supplied on the command line. When the -z stub option is specified to build a stub object, the presence of the STUB_OBJECT directive in a mapfile is required, and the link-editor uses the information in symbol ASSERT attributes to create global symbols that match those of the real object. When the real object is built, the presence of STUB_OBJECT causes the link-editor to verify that the mapfiles accurately describe the real object interface, and that a stub object built from them will provide the same linking interface as the real object it represents. All function and data symbols that make up the external interface to the object must be explicitly listed in the mapfile. The mapfile must use symbol scope reduction ('*'), to remove any symbols not explicitly listed from the external interface. All global data in the object is required to have an ASSERT attribute that specifies the symbol type and size. If the ASSERT BIND attribute is not present, the link-editor provides a default assertion that the symbol must be GLOBAL. If the ASSERT SH_ATTR attribute is not present, or does not specify that the section is one of BITS or NOBITS, the link-editor provides a default assertion that the associated section is BITS. All data symbols that describe the same address and size are required to have ASSERT ALIAS attributes specified in the mapfile. If aliased symbols are discovered that do not have an ASSERT ALIAS specified, the link fails and no object is produced. These rules ensure that the mapfiles contain a description of the real shared object's linking interface that is sufficient to produce a stub object with a completely compatible linking interface. SYMBOL_SCOPE/SYMBOL_VERSION ASSERT Attribute The SYMBOL_SCOPE and SYMBOL_VERSION mapfile directives were extended with a symbol attribute named ASSERT. The syntax for the ASSERT attribute is as follows: ASSERT { ALIAS = symbol_name; BINDING = symbol_binding; TYPE = symbol_type; SH_ATTR = section_attributes; SIZE = size_value; SIZE = size_value[count]; }; The ASSERT attribute is used to specify the expected characteristics of the symbol. The link-editor compares the symbol characteristics that result from the link to those given by ASSERT attributes. If the real and asserted attributes do not agree, a fatal error is issued and the output object is not created. In normal use, the link editor evaluates the ASSERT attribute when present, but does not require them, or provide default values for them. The presence of the STUB_OBJECT directive in a mapfile alters the interpretation of ASSERT to require them under some circumstances, and to supply default assertions if explicit ones are not present. See the definition of the STUB_OBJECT Directive for the details. When the -z stub command line option is specified to build a stub object, the information provided by ASSERT attributes is used to define the attributes of the global symbols provided by the object. ASSERT accepts the following: ALIAS Name of a previously defined symbol that this symbol is an alias for. An alias symbol has the same type, value, and size as the main symbol. The ALIAS attribute is mutually exclusive to the TYPE, SIZE, and SH_ATTR attributes, and cannot be used with them. When ALIAS is specified, the type, size, and section attributes are obtained from the alias symbol. BIND Specifies an ELF symbol binding, which can be any of the STB_ constants defined in <sys/elf.h>, with the STB_ prefix removed (e.g. GLOBAL, WEAK). TYPE Specifies an ELF symbol type, which can be any of the STT_ constants defined in <sys/elf.h>, with the STT_ prefix removed (e.g. OBJECT, COMMON, FUNC). In addition, for compatibility with other mapfile usage, FUNCTION and DATA can be specified, for STT_FUNC and STT_OBJECT, respectively. TYPE is mutually exclusive to ALIAS, and cannot be used in conjunction with it. SH_ATTR Specifies attributes of the section associated with the symbol. The section_attributes that can be specified are given in the following table: Section AttributeMeaning BITSSection is not of type SHT_NOBITS NOBITSSection is of type SHT_NOBITS SH_ATTR is mutually exclusive to ALIAS, and cannot be used in conjunction with it. SIZE Specifies the expected symbol size. SIZE is mutually exclusive to ALIAS, and cannot be used in conjunction with it. The syntax for the size_value argument is as described in the discussion of the SIZE attribute below. SIZE The SIZE symbol attribute existed before support for stub objects was introduced. It is used to set the size attribute of a given symbol. This attribute results in the creation of a symbol definition. Prior to the introduction of the ASSERT SIZE attribute, the value of a SIZE attribute was always numeric. While attempting to apply ASSERT SIZE to the objects in the Solaris ON consolidation, I found that many data symbols have a size based on the natural machine wordsize for the class of object being produced. Variables declared as long, or as a pointer, will be 4 bytes in size in a 32-bit object, and 8 bytes in a 64-bit object. Initially, I employed the conditional $if directive to handle these cases as follows: $if _ELF32 foo { ASSERT { TYPE=data; SIZE=4 } }; bar { ASSERT { TYPE=data; SIZE=20 } }; $elif _ELF64 foo { ASSERT { TYPE=data; SIZE=8 } }; bar { ASSERT { TYPE=data; SIZE=40 } }; $else $error UNKNOWN ELFCLASS $endif I found that the situation occurs frequently enough that this is cumbersome. To simplify this case, I introduced the idea of the addrsize symbolic name, and of a repeat count, which together make it simple to specify machine word scalar or array symbols. Both the SIZE, and ASSERT SIZE attributes support this syntax: The size_value argument can be a numeric value, or it can be the symbolic name addrsize. addrsize represents the size of a machine word capable of holding a memory address. The link-editor substitutes the value 4 for addrsize when building 32-bit objects, and the value 8 when building 64-bit objects. addrsize is useful for representing the size of pointer variables and C variables of type long, as it automatically adjusts for 32 and 64-bit objects without requiring the use of conditional input. The size_value argument can be optionally suffixed with a count value, enclosed in square brackets. If count is present, size_value and count are multiplied together to obtain the final size value. Using this feature, the example above can be written more naturally as: foo { ASSERT { TYPE=data; SIZE=addrsize } }; bar { ASSERT { TYPE=data; SIZE=addrsize[5] } }; Exported Global Data Is Still A Bad Idea As you can see, the additional plumbing added to the Solaris link-editor to support stub objects is minimal. Furthermore, about 90% of that plumbing is dedicated to handling global data. We have long advised against global data exported from shared objects. There are many ways in which global data does not fit well with dynamic linking. Stub objects simply provide one more reason to avoid this practice. It is always better to export all data via a functional interface. You should always hide your data, and make it available to your users via a function that they can call to acquire the address of the data item. However, If you do have to support global data for a stub, perhaps because you are working with an already existing object, it is still easilily done, as shown above. Oracle does not like us to discuss hypothetical new features that don't exist in shipping product, so I'll end this section with a speculation. It might be possible to do more in this area to ease the difficulty of dealing with objects that have global data that the users of the library don't need. Perhaps someday... Conclusions It is easy to create stub objects for most objects. If your library only exports function symbols, all you have to do to build a faithful stub object is to add STUB_OBJECT; and then to use the same link command you're currently using, with the addition of the -z stub option. Happy Stubbing!

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  • How do I free SQLServerCE's COM instance from the current running process?

    - by David Thornley
    It's been a while since I touched COM so be nice ;) This is under WindowsCE 5.0 with SQLServerCE 2.0. After calling this to load SQLServerCE 2.0 : - IDBInitialize *pIDBInitialize = NULL; CoCreateInstance(CLSID_SQLSERVERCE_2_0, NULL, CLSCTX_INPROC_SERVER, IID_IDBInitialize, (void**)&pIDBInitialize); Module load occurs for SSCE20.dll which obviously loads the SQLServerCE engine into the process space. What I don't understand is if I do this immediately after :- pIDBInitialize->Release(); I don't see a dll module unload, so that SSCE20.dll (and friends) are still loaded into my process. Now I tried CoFreeUnusedLibraries() which I figure forces COM to purge any unused libraries, but it doesn't seem to do the trick. At runtime I want to be able to completely unload the SQLServerCE 2.0 dll from the process to streamline an upgrade to 3.5SP1. I suspect this has something to do with the shared dll model that Microsoft use under WindowsCE... but, I might be wrong :) Thanks in advance, David.

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