C Interviews
C Interview
The following are the salient features of C language are : ? C is called a middle level language ? C supports structured design approach ? C is extensible ? C is rich in data types and operators ? C is portable
Header files provide the definitions and declarations for the library functions. Thus, each header file contains the library functions along with the necessary definitions and declarations. For example, stdio.h, math.h, stdlib.h, string.h etc.
Character set is the set of characters allowed and supported in the programming language. Generally a program is a collection of instructions, which contain groups of characters. Only a limited set of characters is allowed to write instructions in the program.
The smallest individual units of a C program are known as tokens. ? Constants ? Identifiers ? Keywords ? Operators ? Special symbols ? Strings
A string is a sequence of characters ending with NUL. It can be treated as a one?dimensional array of characters terminated by a NUL character.
Qualifiers or modifiers are identifiers that may precede the scalar data types (except float) to specify the number of bits used for representing the respective type of data in memory. The qualifiers in C are short, long, signed, and unsigned
A constant is a value that does not change during the program execution. A constant used in C does not occupy memory.
There are five types of constants. They are : ? Integer constants ? Floating point constants ? Character constants ? String literals ? Enumeration constants
? The first character must be an alphabet or underscore (_) ? Digits may be included in the variable ? The maximum number of characters in a word are 32 (It may vary depending upon the platform) ? No other special characters are allowed.
Global Variables are those, which are required to be acccessed by all the functions defined after their declaration. So, the variables declared before the main {) can be acccessed by all the functions, which follow their declaration.