Interview Q&A

• How can a parent and child process communicate?

  A parent and child can communicate through any of the normal inter-process communication schemes (pipes, sockets, message queues, shared memory), but also have some special ways to communicate that take advantage of their relationship as a...

• Explain fork() system call.

  The `fork()' used to create a new process from an existing process. The new process is called the child process, and the existing process is called the parent. We can tell which is which by checking the return value from `fork()'. The paren...

• Discuss the mount and unmount system calls

  The privileged mount system call is used to attach a file system to a directory of another file system; the unmount system call detaches a file system. When you mount another file system on to your directory, you are essentially splicing on...

• How are devices represented in UNIX?

  All devices are represented by files called special files that are located in/dev directory. Thus, device files and other files are named and accessed in the same way. A 'regular file' is just an ordinary data file in the disk. A 'block spe...

• What is use of sed command?

  ed reads the standard input into the pattern space, performs a sequence of editing commands on the pattern space, then writes the pattern space to STDOUT.

• Should I use CGI or an API?

  APIs are proprietary programming interfaces supported by particular platforms. By using an API, you lose all portability. If you know your application will only ever run on one platform (OS and HTTPD), and it has a suitable API, go ahead an...

• What is the "CGI Overhead", and should I be worried about it?

  The CGI Overhead is a consequence of HTTP being a stateless protocol. This means that a CGI process must be initialised for every "hit" from a browser. In the first instance, this usually means the server forking a new process. This in itse...

• Do I need to be on Unix?

  No, but it helps. The Web, along with the Internet itself, C, Perl, and almost every other Good Thing in the last 20 years of computing, originated in Unix. At the time of writing, this is still the most mature and best-supported platform f...

• Do I need to be on Unix?

  No, but it helps. The Web, along with the Internet itself, C, Perl, and almost every other Good Thing in the last 20 years of computing, originated in Unix. At the time of writing, this is still the most mature and best-supported platform f...

• What do I need to know about file permissions and "chmod"?

  Unix systems are designed for multiple users, and include provision for protecting your work from unauthorised access by other users of the system. The file permissions determine who is permitted to do what with your programs, data, and dir...

• What do I need to know about file permissions and "chmod"?

  Unix systems are designed for multiple users, and include provision for protecting your work from unauthorised access by other users of the system. The file permissions determine who is permitted to do what with your programs, data, and dir...

• How do I decode the data in my Form?

  The normal format for data in HTTP requests is URLencoded. All Form data is encoded in a string, of the form param1=value1&param2=value2&...paramn=valuen Many non-alphanumeric characters are "escaped" in the encoding: the character whose he...

• What is CGI?

  he Common Gateway Interface, or CGI, is a standard for external gateway programs to interface with information servers such as HTTP servers. A plain HTML document that the Web daemon retrieves is static, which means it exists in a constant...

• What are the default Oracle triggers??

  Default triggers in oracle are nothing but Constraints.Constraints are the triggers which are executed automatically at the time of DML operations.

• When do I need to use CGI?

  There are innumerable caveats to this answer, but basically any Webpage containing a form will require a CGI script or program to process the form inputs.

• How to set a shortcut key for label?

  object.KeyLabel(keycode) [= string] You would probably create the menu item as follows: .Add "keyFile", , , "E&xit", , vbAltMask + vbCtrlMask, vbKeyEnd The default key label for vbKeyEnd is "End". Thus, the shortcut string will be create...

• What is the tool used to configure the port range and protocols for DCOM communications?

  DCOMCONFIG.EXE

• Difference between Query unload and unload in form?

  Occurs before a form or application closes. When an MDIForm object closes, the QueryUnload event occurs first for the MDI form and then in all MDI child forms. If no form cancels the QueryUnload event, the Unload event occurs first in all o...

• Difference modal and moduless window?

  MODAL forms are forms which require user input before any other actions can be taken place. In other words, a modal form has exclusive focus in that application until it is dismissed. When showing a modal form, the controls outside this mo...

• Difference between listbox and combo box?

  A LISTBOX CONTROL displays a list of items from which the user can select one or more. If the number of items exceeds the number that can be displayed, a scroll bar is automatically added to the ListBox control. A COMBOX CONTROL combines th...

• Default property of datacontrol ?

  connect property.

• Controls which do not have events?

  Shape and line controls are useful for drawing graphical elements on the surface of a form. These controls don't support any events; they are strictly for decorative purposes.

• How to register a component?

  Compiling the component, running REGSVR32 MyDLL.dll

• What is a Component?

  If you compile an ActiveX dll, it becomes a component. If you compile an ActiveX Control, it becomes both a component and a control. Component is a general term used to describe code that's grouped by functionality. More specifically, a co...

• How many event in VB6 form.

  31

• How many event in VB6 form.

  31

• WhatisOLEDB?

  Object Linking and Embeded DataBase.oledb is an activex control that allows other application to be embedded in user's built vb application

• What is early binding and late binding ?

  early binding: eg: dim rs as new adodb.recordset Late Binding: eg: dim rs as adodb.recordset set rs=new adodb.recordset

• What is MAPI?

  Messaging Application programing Interface.

• what is visual basic?

  vb graphical user interface which can help the use which easy understand

• What is the difference between far and near?

  far pointers are 32 bits long and can address a 1MB range.Near pointers operate within a 64KB segment. There’s one segment for function addresses and one segment for data. far pointers have a 16-bit base (the segment address) and a 16-bit o...

• Is using exit() the same as using return?

  No. The exit() function is used to exit your program and return control to the operating system. The return statement is used to return from a function and return control to the calling function.

• Can the sizeof operator be used to tell the size of an array passed to a function?

  No. There’s no way to tell, at runtime, how many elements are in an array parameter just by looking at the array parameter itself. Remember, passing an array to a function is exactly the same as passing a pointer to the first element.

• What are the advantages of the functions?

  Ø Debugging is easier Ø It is easier to understand the logic involved in the program Ø Testing is easier Ø Recursive call is possible

• How are pointer variables initialized?

  Pointer variable are initialized by one of the following two ways Ø Static memory allocation Ø Dynamic memory allocation

• When would you use a pointer to a function?

  Pointers to functions are interesting when you pass them to other functions. A function that takes function pointers says, in effect, “Part of what I do can be customized.

• How do you reverse a linked list without using any C pointers?

  One way is to reverse the data in the nodes without changing the pointers themselves. One can also create a new linked list which is the reverse of the original linked list. A simple C program can do that for you. Please note that you would...

• What is a memory leak?

  Its an scenario where the program has lost a reference to an area in the memory. Its a programming term describing the loss of memory. This happens when the program allocates some memory but fails to return it to the system

• What is a NULL pointer?

  A null pointer simply means "I am not allocated yet!" and "I am not pointing to anything yet!". The C language definition states that for every available pointer type, there is a special value which is called the null pointer. It is guaran...

• What are macros ?

  Macros are preprocessors which are small code of snippets which are replaced in the code AS IT IS before compilation of the program.

• what is lisp?

  LISP is an acronym for LISt Processing. Its development history has often been associated with symbolic processing and with both computer and human languages. A heterogeneous list data type has always been built into the language in order t...

• 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.

• 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?

  Forth's interactive nature streamlines the test and development of new hardware. Incremental development, a fast program-debug cycle, full interactive access to any level of the program, and the ability to work at a high "level of abstracti...

• 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,...

• How is OnCalcFields event handler used in Delphi?

  OnCalculate is event in Delphi it trigerrs when you are reading data from the database.

• What are Delphi units?

  Unit is nothing but a text file that can be complied in a module of code.there are 2 different types of units Project Source unit and it can be saved with an extension of .DPRand Source code unit with an associated form.

• What is the use of unit interface section of Delphi?

  Every identifier (type, routine, variable, and so on) that you declare in the Interface portion of a unit becomes visible to any other unit of the program.

• What is the use of TActiveForm object in Delphi?

  TActiveForm is the base class for a VCL Form exposed as an ActiveX control. TActiveForm represents a form that is created by a class factory (in Delphi) or using the Active Template Library (C++) and used as an ActiveX control in ActiveX ho...

• What is the use of GlobalMemoryStatus() function in Delphi?

  It is a function in Delphi to find the Total memory status.It accepts TMemoryStatus variable as var parameter.It fills the variable entity with different memory status info like Total phisical Memory