c

JThreads/C++ is a Java like threads for C++.

A unique and very useful product, JThreads/C++ is a portable thread abstraction library that mimics the thread classes and primitives found in JavaTM. Supported on Windows 95, NT and many flavors of Unix, JThreads/C++ simplifies the development of multi-threaded applications by encapsulating all platform-specific function calls inside a well-designed, easy-to-use class library.

How Does It Work?

Java’s support for multi-threaded programming is provided by the following constructs:

The classes java.lang.Thread and java.lang.ThreadGroup
The interface java.lang.Runnable
The synchronized keyword
The methods wait, notify and notifyAll in java.lang.Object

The Java classes java.lang.Thread and java.lang.ThreadGroup are directly translated into the C++ classes JTCThread and JTCThreadGroup. The only difference is that the JThreads/C++ classes have JTC as a prefix instead of the Java package java.lang. The Java interface java.lang.Runnable is implemented as the abstract C++ class JTCRunnable, which contains the pure virtual method run.

Support for the synchronized keyword is slightly more difficult, since it is not possible to add new keywords to C++. JThreads/C++ addresses this issue using two additional classes, JTCMonitor and JTCSynchronized, wich together form the replacement for the synchronized keyword. JTCMonitor also provides the methods wait, notify and notifyAll.

mod_diagnostics is a debugging and diagnostic tool for application developers - particularly filter modules.

mod_diagnostics.c can be inserted anywhere in the Apache filter chain, and logs traffic (buckets and brigades) passing through.

It is a purely passive watcher, and will never touch the traffic passing through.

Examples

Probably the best way to explain mod_diagnistics is by example.

Strange delays in some browsers

In an update to mod_xml, a new bug was introduced. It was not immediately obvious, but in some browsers the request would hang and then timeout. The effect was only observed when using the XSLT output filter with Xalan-C, and only happened with HTTP/1.1 browser, not with HTTP/1.0. Furthermore, hitting "cancel" before the timeout in an HTTP/1.1 browser would cause the page to display!
Inserting mod_diagnostics before and after the offending filter, the bug was immediately obvious. The module was simply failing to pass an EOS bucket down the chain. A trivial fix!

Obscure bug in a third-party library

A user of mod_proxy_html reported serious performance problems when parsing an 8Mb HTML file. He had profiled the problem, and found the entire processing time was in the final call to htmlParseChunk in libxml2.

I investigated this by inserting mod_diagnostics before and after mod_proxy_html, and running it with the largest HTML document I had available (the MySQL manual, about 2.6Mb). I was able to confirm that nothing was passed down the chain until the final call, so not only was it slow, but it had also broken Apache pipelining.

To refine the diagnosis, I added a flush in each call to the filter in mod_proxy_html. Now mod_diagnostics showed a small amount of data (under 1Kb) coming through in the first call to the filter, but nothing else until the end. Further investigation showed that the data stopped coming when the first HTML comment was encountered in the source.

At this point I ran it under gdb, looking for the comment handling. I found that it was failing to find the end of the comment. The problem was resolved only in the last call to htmlParseChunk, which didnt go through the buggy code. I disabled the buggy code, and found it was now working correctly, with approximately the same amount of input and output data in each call to the mod_proxy_html filter - so pipelining was now fixed. My correspondent reported total processing Time for his 8Mb file reduced from 30 minutes to 9 seconds (on five-year-old hardware).

The bug was reported to the libxml team, who have now fixed it.

C to C++ is a Python script that converts C code to C++ code.

The main program is ctocpp.py that performs successive stages for converting C to C++. A script, ctocpp gives it as parameter to the python interpreter with options you add.

The archive also includes scripts that may help you:

- mover.py changes the location of a project.
- search.py performs searches and replacements.
- mkheader.py corrects a header file.

The C to C++ program with all the python sources is under the GNU GPL license,
that minds you may use it and distribute it freely, providing the copyright is unchanged.

See at the COPYING file for details. This doesnt mean GNU encourages you to convert your C sources to C++. In fact, most of the tools here included may help C programmers outside C++ conversion.

Installing:

Type:
./configure
./setup
mkdoc ...this will generate an html and info manuals.

*C/C++ interpreter

Ch supports C99 and C++ classes. Ch supports many industry standards with over 8,000 functions including POSIX, socket/Winsock, X11/Motif, OpenGL, ODBC, C LAPACK, GTK+, Win32, and CGI.

* Shell programming and cross-platform scripting

Ch shell is C compatible shell while C-shell (csh) is a C like shell. Ch is an interpretive implementation of C, similar to Unix/MS-DOS shells. Ch in Windows includes over 100 commonly-used Unix commands for portable shell programming. Ch can also be used as a login shell just like sh, csh and ksh. Ch bridges the gap between the C language and shell languages. With its built-in string type and many enhanced scripting features, Ch is an alternative to other scripting languages for automating repetitive tasks, regression test, and hardware testing.

* 2D/3D plotting and numerical computing

Ch supports 2D/3D graphical plotting, C LAPACK, high level numeric functions.
Ch has built-in 2D/3D plotting support, generic mathematical functions and computational arrays for linear algebra and matrix computations, and advanced high-level numerical functions for linear systems, differential equation solving, Fourier analysis, curve fitting, etc.

*Interface with binary C/C++ libraries

Ch SDK 4.5 can easily integrate the existing C/C++ libraries as part of Ch sripting module. Functions and classes in static or dynamical libraries can be invoked in a Ch script file or Ch command shell.

* Embeddable scripting

Ch 4.5 is optimized for embedded scripting. Embedded Ch allows users to embed Ch into other C/C++ application programs and hardware. It is ideal for game and open-architecture application integration. With Embedded Ch, C/C++ applications can be extended with all features of Ch. It allows execution of C/C++ scripts generated dynamically on-line. Embedded Ch has a small footprint.

Lufs::C is a C interface to perl.

ABSTRACT

This interface is used by the C code to call the perl subs.

SEE ALSO

perlfs.c

Env::C is a Get/Set/Unset Environment Variables on the C level.

SYNOPSIS

use Env::C;

my $key = "USER";
$val = Env::C::getenv($key) || ;

Env::C::setenv($key, "foobar", [$override]);
$new_val = Env::C::getenv($key) || ;

Env::C::unsetenv($key);

my $ar_env = Env::C::getallenv();
print join "n", @$ar_env;

This module provides a Perl API for getenv(3), setenv(3) and unsetenv(3). It also can return all the environ variables.

Sometimes Perl invokes modules with underlaying C APIs which rely on certain environment variables to be set, if these variables are set in Perl and the glue code doesnt worry to set them on the C level, these variables might not be seen by the C level. This module shows what really the C level sees.