FAQs

• Language support C?

  C is the language in which the GNOME libraries are written, and therefore has full support. Glade supports it.

• Is there a GUI-builder available for developing gtk/gnome applications?

  The most widely used tool is Glade. A list of all the GTK+ GUI Builder Projects can be found on the GTK+ web site.

• How do I compile & link a simple one-file GNOME program?

  gcc -o simple simple.c `gnome-config --cflags --libs gnomeui`

• How do I issue a command to the operating system within a Fortran program?

  There is no standard way to do this in Fortran, but many compilers have an extension named "system" or something similar. Please consult the documentation of your compiler. In Fortran 2003, one can call C code, and it is possible to call th...

• How do I create numbered file names such as out_01.txt, out_02.txt etc.?

  Use an "internal write" to create the file names, for example write (file_name,"('out_',i2.2,'.txt')") i

• What Fortran compiler should I use?

  G95, Gfortran, and Silverfrost (Windows only) are free Fortran 95 compilers, and Absoft, IBM, Intel, Lahey, NAG, Pathscale, PGI, and Sun sell Fortran compilers. Comparative information on Fortran compilers from Polyhedron Software is availa...

• Should I learn Fortran? Is it obsolete?

  Fortran is a good language for scientific programming, because it is fast, is good at handling arrays, is standardized, is portable, and because many high-quality libraries of numerical algorithms exist. The language itself is also maintain...

• Where can I find a f90 tutorial or course?

  http://www.academictutorials.com/fortran/

• Who creates these silly standards anyway?

  Typically X3J3. X3J3 is an ANSI subcommittee dedicated to Fortran. WG5 is the ISO counterpart. WG5 owns responsibility for Fortran on an international basis. WG5 has previously tasked X3J3 to do the work. This arrang...

• How does Fortran 90 relate to FORTRAN '77?

  With a few minor exceptions, Fortran 90 is a superset of X3.9-1978 FORTRAN. But this does not mean that all "77" codes will port sans changes. Many (if not most) programmers employed constructs beyond the '77...

• How does the Fortran 90 interface differ from the C interface?

  The Fortran 90 interface provides the same functionality as the FORTRAN and C interfaces, but the interface is substantially smaller. We've done this by using optional arguments in the file, dimension, variable, and attribute inquire functi...

• How does the FORTRAN interface differ from the C interface?

  It provides all the functionality of the C interface. The FORTRAN interface uses FORTRAN conventions for array indices, subscript order, and strings. There is no difference in the on-disk format for data written from the different language...

• Can I use DLLs developed in C or C++ from Delphi?

  Delphi is capable of making calls to and receiving callbacks from any standard Windows DLL. In addition, it is said to be possible (though rather tricky) to get Delphi to access classes within C++ DLLs. Borland's WWW server has...

• What source management tools are compatible with Delphi?

  Delphi Client/Server is said to include built-in connectivity to PVCS. In addition, it should be possible to connect to most non-language-specific source control systems. However, Delphi forms are stored in non-text format, so a...

• I just bought Delphi. Where are the language and library reference

  They don't ship those manuals with Delphi because of their size. The component library reference is over 1000 pages. You can get all this information from the on-line help, or you can ftp the manuals from Borland in Acrobat fo...

• What if I don't have a CD-ROM drive?

  Borland will ship Delphi on 3.5" floppy diskettes, but they charge extra for them. The resellers I have spoken to only carry the CD-ROM version because they don't want to have to stock two different items. I got my copy on CD, b...

• Where can I get a copy of Delphi?

  If you are in the US, You can order Delphi Desktop on CD-ROM for an introductory price of $199 by calling Borland's credit card order desk at 1-800-331-0877. If you are a registered user of any version of Turbo Pascal or Borland...

• What is the history of Delphi?

  Delphi is the descendant of Turbo Pascal, which was first released in 1983 for the CP/M operating system. Turbo Pascal was ported to MS-DOS in early 1984. During the early history of the IBM PC, Turbo Pascal was arguably the mos...

• How tough is it to learn Delphi?

  If you're lucky, you already have lots of experience with both Object Pascal (or, as it used to be called, Borland Pascal With Objects-- essentially, Turbo Pascal v5.5 or later) and with Visual Basic. If you fit this description...

• How much disk space, memory, etc., do I need to run Delphi?

  The minimum installation of Delphi takes about 30Mb, and the full install takes 80Mb. In order to run it well, you'll need a 486 with a minimum of 8Mb of RAM, though I personally wouldn't try to run it in less than about 12Mb. I...

• What versions of Delphi are there?

  Delphi has been available in beta-test for many months now, and Borland has also given away a large number of "prerelease" copies. As far as the official release is concerned, though, there are two packages: Delphi (sometimes re...

• What is Delphi?

  Delphi is a product of Borland International. It is a native code compiler that runs under Windows 3.1 and provides visual programming tools somewhat similar to those found in Microsoft Visual Basic 3.0. The underlying language...

• Why can't I apply #'AND or #'OR?

  Here's the simple, but not necessarily satisfying, answer: AND and OR are macros, not functions; APPLY and FUNCALL can only be used to invoke functions, not macros and special operators. OK, so what's the real reason? The reason that AND...

• Does anyone actually use flet?

  This question is usually motivated by the existence of labels, which is a similar form for binding functions, but also allows mutual recursion between the functions being bound. Given this, it is perhaps natural to question the utility of f...

• How does (defun car (x) (car x)) work?

  This code is probably part of the source to a lisp compiler, which knows how to open-code calls to CAR. However, the interpreter also needs to know how to call CAR, which is what the above defun is doing. This is not recommended in user cod...

• Why doesn't Common Lisp have continuations?

  Continuations are a great theoretical tool; if a language has first-class, multiply invocable continuations then one can build threads, exceptions, coroutines, and the kitchen sink on top. However, there is an implementation burden with...

• How do I split a string?

  There is no `right' answer to this question; many lisp programmers have rolled their own solution in the past, and others are of the view that it should never be necessary, as long as all sequence functions are used with consistent :start a...

• How do I write a "Hello, World!" programme in Lisp?"

  This is actually a subtle question; not in the respect of computing "Hello, World!", obviously, but because of what being a "Hello, World!" programme actually means. At its simplest, you can simply type "Hello, World!" at the REPL, to fi...

• Is Scheme a lisp?

  Scheme is a member of the greater family of Lisp languages, assuming that is considered to include others like Dylan and Emacs Lisp. The design of Scheme predates the ANSI Common Lisp standard, and some CL features such as lexical scoping m...

• What is off-topic on comp.lang.lisp?

  Questions about Scheme, Emacs Lisp and AutoLisp tend not to be terribly welcome, as they have their own fora in the comp.lang.scheme, comp.emacs and comp.cad.autocad newsgroups.

• What is on-topic on comp.lang.lisp?

  Disscussion of the language defined by the ANSI Common Lisp standard is definitely on-topic on comp.lang.lisp. Unlike comp.lang.c, we do not restrict our discussions to the standard, but also actively discuss the differences between impleme...

• What is the purpose of comp.lang.lisp?

  It is somewhat in the nature of things that newsgroups' purposes evolve, as do names. Firstly, the newsgroup has evolved such that the main topic of discussion is ANSI Common Lisp, though discussion about other lisp variants is welcome with...

• Free Forth systems are bad for Forth.

  "Anyone can write a bad Forth and give it away without documentation or support; after trying such a system, nobody wants to work with Forth anymore. Free Forths give Forth a bad name. Free Forths take business away from the vendors." "M...

• Commercial vs. free Forth systems

  "You get what you pay for. With a commercial Forth you get commercial documentation and support. We need commercial Forth systems or Forth will die." "I have had good experiences with free Forths. I cannot afford a commercial Forth syste...

• When I redefine a word, old uses refer to the old definition. How do I ...?

  That behaviour is known as early binding (of names), and it is a feature: E.g., name collisions are mostly harmless in Forth, unlike most other languages. So how do I change a word during debugging? The typical approach is to completely...

• What is the Forth Interest Group?

  The Forth Interest Group "FIG" was formed in 1978 to disseminate information and popularize the Forth language, and it remains the premier organization for professional Forth programmers.

• What is an RFI?

  A Request For Interpretation. If you find something in the standard document ambiguous or unclear, you can make an RFI, and the TC (technical committee), that produced the standard, will work out a clarification.

• What language standards exist for Forth?

  An American National Standard for Forth, ANSI X3.215-1994, is accepted worldwide as the definitive Forth standard ("ANS Forth"). This standard also has been blessed as international standard (ISO/IEC 15145:1997).

• Is Forth faster or smaller than C?

  Not in itself. I.e., if you translate a C program literally into Forth, you will see a slow-down (e.g., a factor 4-8 with Gforth 0.5, a threaded-code system; for typical native-code systems you will see a factor of 1-3). Similarly, there is...

• Why and where is Forth used?

  Although invented in 1970, Forth became widely known with the advent of personal computers, where its high performance and economy of memory were attractive. These advantages still make Forth popular in embedded microcontroller systems, in...

• Where does the name Forth come from?

  The name FORTH was intended to suggest software for the fourth (next) generation computers, which Moore saw as being characterized by distributed small computers. The operating system he used at the time restricted file names to five charac...

• What is Forth?

  Forth is a stack-based, extensible programming language without type-checking. It is probably best known for its "reverse Polish" (postfix) arithmetic notation, familiar to users of Hewlett-Packard calculators: to add two numbers in Forth,...

• Can I use a named pipe across NFS?

  No, you can't. There is no facility in the NFS protocol to do this. (You may be able to use a named pipe on an NFS-mounted filesystem to communicate between processes on the same client, though.)

• How do I use a named pipe?

  To use the pipe, you open it like a normal file, and use read() and write() just as though it was a plain pipe.

• How do I create a named pipe?

  To create a named pipe interactively, you'll use either mknod or mkfifo. On some systems, mknod will be found in /etc. In other words, it might not be on your path.

• What is a named pipe?

  A named pipe is a special file that is used to transfer data between unrelated processes. One (or more) processes write to it, while another process reads from it. Named pipes are visible in the file system and may be viewed with `ls' li...

• How to manage multiple connections?

  Use select() or poll().

• How do I use poll()?

  poll() accepts a pointer to a list of struct pollfd, in which the descriptors and the events you wish to poll for are stored. The events are specified via a bitwise mask in the events field of the structure. The instance of the structure...

• How do I use select()?

  The interface to select() is primarily based on the concept of an fd_set, which is a set of FDs (usually implemented as a bit-vector). In times past, it was common to assume that FDs were smaller than 32, and just use an int to store the...

• What is a zombie?

  When a program forks and the child finishes before the parent, the kernel still keeps some of its information about the child in case the parent might need it -- for example, the parent may need to check the child's exit status. To be ab...