C Language INTERVIEW QUESTION & ANSWERS
51. |
What is a pointer? |
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A pointer is a variable that represents the location (rather than the value) of a data item, such as a variable or an array element. It is a variable that holds a memory address. This address is the location of another variable or an array element in memory. |
52. |
How to declare pointer variables? |
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If a variable is going to be a pointer, it must be declared as such. A pointer declaration consists of a base type, an *, and the variable name. The general form for declaring a pointer variable is data _type * var_ name;
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53. |
What is the difference between fread buffer() and fwrite buffer()? |
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Fread(), buffer is a pointer to an area of memory that will receive the data from the file. For fwrite(), buffer is a pointer to the information that will be written to the file. The value of count determines how many items are read or written, with each item being num_byte bytes in length. The size_t in both the formats is defined as some kind of unsigned integer. Finally, fp is a file pointer to a previously opened file.
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54. |
What is macro? |
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The second preprocessor function is macro definition. A macro is formal syntax that can be used to generate statements for use in a program. For the C language, the macro generates C statements. |
55. |
What are the types of I/O functions? |
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I/O functions are grouped into two categories :
- Unformatted I/O functions
- Formatted I/O functions
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