Preprocessing Directives
Introduction C’s preprocessor provides a facility for defining constant and substitution, which are commonly called […]
Preprocessor Directives in C
undef directive
If you want to nullify the effect of the define directive and specify a new […]
ifdef
The ifdef directive makes substitutions based on whether a particular identifier is defined. Example
ifndef
#ifndef is used to check whether a particular symbol is NOT defined. Example
#if
#if allows you to define more generalized conditions. Multiple conditions, which are connected by relational […]
ifelse
The ifelse directive lets us specify the action if the condition is not true. Example […]
ifelif
ifelif allows us to take one action if there are multiple decision points. For example, […]
Error Directive
The error directive is used to specify an error message for a specific situation. In […]
#line
The #line directive allows you to define arbitrary line numbers for the source lines. Normally, […]
Macros in C
Macros allow replacement of the identifier by using a statement or expression. The replacement text […]
Macros and Functions
While writing the macro, you have to write the macro body carefully because the macro […]
Getting file name and path in C/C++
The standard predefined MACRO __FILE__ available in C shows the full path to the file.
getting system date in C
__DATE__ macro is used to print system date in C/C++ language. This macro expands to […]
Getting system time in C/C++
__TIME__ macro is used to print system time in C/C++ language. This macro expands to […]