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This C tutorial explains how to use the #endif preprocessor directive in the C language. In the C Programming Language, the #endif directive closes off the following directives: #if, #ifdef, or #ifndef. endif-line: #endif. Each #if directive in a source file must be matched by a closing #endif directive. Any number of #elif directives can appear between the #if and #endif directives, but at most one #else directive is allowed. The #else directive, if present, must be the last directive before #endif. #if statement: Conditional Compilation Directives (C Preprocessor) What #if statement do? These Conditional Compilation Directives allow us to include certain portion of the code depending upon the output of constant expression Syntax: #if Expression Statement 1 Statement Statement n #endif Explanation: #if Statement Expression allows only constant expression [ ]. C language #ifdef, #else, #endif Pre-processor with Example. #ifdef, #else, #endif. The directives #ifdef, #else and #endif are logical pre-processor directives which are used to specify which code will be compiled through the compiler based on defined macros. C Pre-Processors, #if, #define, #elseif, #endif and #include - Free tutorial and references for ANSI C Programming. You will learn ISO GNU K and R C99 C Programming computer language in easy steps. C is the most popular system programming and widely used computer language in the computer world.Browse the most interesting profiles of mature MILFs, Housewives and Cougars. Your future is in your own hands, we will provide a caring and focused milf sex dating service that will allow you to find that special someone who share your sexual interests. MILF housewife phonesex, bored MILFS home alone, nasty cheating MILF mums hot phone sex chat I'm a 50 plus MILF and cheating housewife - gagging for a satisfying shag. I'm a sexually experienced 50 plus older babe who loves to suck and fuck any stiff dick ready to penetrate my tight ass-hole and gagging for it mature pussy. Anal, oral, group sex, dogging - whatever, whenever. I'm up for fun. I'm ready for some kinky sex action. If Else Statement in C (HINDI/URDU) Hot MILFS and cougars for filthy 121 adult sex chat. Call or text now. Discover the growing collection of high quality Most Relevant XXX movies and clips. Get off with the UK sexy MILFs in just minutes for adult chat. With so many MILFs to if endif c example s from there is bound to be one for you. Contact REAL MILFs in seconds and start MILF Sex Chat now. It's every guys dream, a woman with a exmaple drive that can match their own.
The preprocessor provides the ability for the inclusion of header files , macro expansions, conditional compilation , and line control. In many C implementations, it is a separate program invoked by the compiler as the first part of translation.
The language of preprocessor directives is only weakly related to the grammar of C, and so is sometimes used to process other kinds of text files. Its original version allowed only to include files and perform simple string replacements: include and define of parameterless macros. Soon after that, it was extended, mostly by Mike Lesk and then by John Reiser, to incorporate macros with arguments and conditional compilation.
C preprocessor was part of a long macro-language tradition at Bell Labs, which was started by Douglas Eastwood and Douglas McIlroy in Preprocessing is defined by the first four of eight phases of translation specified in the C Standard.
This can also be written using double quotes, e. If the filename is enclosed within angle brackets, the file is searched for in the standard compiler include paths. If the filename is enclosed within double quotes, the search path is expanded to include the current source file directory. C compilers and programming environments all have a facility which allows the programmer to define where include files can be found.
This can be introduced through a command line flag, which can be parameterized using a makefile , so that a different set of include files can be swapped in for different operating systems, for instance.
By convention, include files are named with either a. However, there is no requirement that this be observed. Files with a. The if-else directives if , ifdef , ifndef , else , elif and endif can be used for conditional compilation.
A few compilers define WIN32 instead. There are two types of macros, object-like and function-like. Object-like macros do not take parameters; function-like macros do although the list of parameters may be empty. The generic syntax for declaring an identifier as a macro of each type is, respectively:. The function-like macro declaration must not have any whitespace between the identifier and the first, opening, parenthesis. If whitespace is present, the macro will be interpreted as object-like with everything starting from the first parenthesis added to the token list.
Whenever the identifier appears in the source code it is replaced with the replacement token list, which can be empty. For an identifier declared to be a function-like macro, it is only replaced when the following token is also a left parenthesis that begins the argument list of the macro invocation. The exact procedure followed for expansion of function-like macros with arguments is subtle.
Object-like macros were conventionally used as part of good programming practice to create symbolic names for constants, e. This causes the value to be stored in memory, instead of being substituted by the preprocessor. This defines a radians -to-degrees conversion which can be inserted in the code where required, i.
This is expanded in-place, so that repeated multiplication by the constant is not shown throughout the code. The macro here is written as all uppercase to emphasize that it is a macro, not a compiled function. The second x is enclosed in its own pair of parentheses to avoid the possibility of incorrect order of operations when it is an expression instead of a single value.
Similarly, the outer pair of parentheses maintain correct order of operation. Certain symbols are required to be defined by an implementation during preprocessing. For instance the following:. The line directive determines the line number and the file name of the line below. This allows source code debugging, when C is used as target language of a compiler, for a totally different language. Compilers running in non-standard mode must not set these macros, or must define others to signal the differences.
Macros that can take a varying number of arguments variadic macros are not allowed in C89, but were introduced by a number of compilers and standardised in C Variadic macros are particularly useful when writing wrappers to functions taking a variable number of parameters, such as printf , for example when logging warnings and errors.
One little-known usage pattern of the C preprocessor is known as X-Macros. Commonly these use the extension ". This file contains a list of similar macro calls, which can be referred to as "component macros". The include file is then referenced repeatedly. Many compilers define additional, non-standard macros, although these are often poorly documented. The operator known as the "Stringification Operator" converts a token into a C string literal , escaping any quotes or backslashes appropriately.
If you want to stringify the expansion of a macro argument, you have to use two levels of macros:. You cannot combine a macro argument with additional text and stringify it all together. You can however write a series of adjacent string constants and stringified arguments: the C compiler will then combine all the adjacent string constants into one long string.
Implementations may provide their own extensions and deviations, and vary in their degree of compliance with written standards. Their exact behavior may depend on command-line flags supplied on invocation.
For instance, the GNU C preprocessor can be made more standards compliant by supplying certain flags. The pragma directive is a compiler-specific directive , which compiler vendors may use for their own purposes. For instance, a pragma is often used to allow suppression of specific error messages, manage heap and stack debugging and so on. A compiler with support for the OpenMP parallelization library can automatically parallelize a for loop with pragma omp parallel for.
C99 introduced a few standard pragma directives, taking the form pragma STDC As the C preprocessor can be invoked separately from the compiler with which it is supplied, it can be used separately, on different languages. Notable examples include its use in the now-deprecated imake system and for preprocessing Fortran.
However, such use as a general purpose preprocessor is limited: the input language must be sufficiently C-like. GPP also works acceptably with most assembly languages. This requires that the assembler syntax not conflict with GPP syntax, which means no lines starting with and that double quotes, which gpp interprets as string literals and thus ignores, don't have syntactical meaning other than that.
The C preprocessor is not Turing-complete , but it comes very close: recursive computations can be specified, but with a fixed upper bound on the amount of recursion performed. As the C preprocessor does not have features of some other preprocessors, such as recursive macros, selective expansion according to quoting, and string evaluation in conditionals, it is very limited in comparison to a more general macro processor such as m4. From Wikipedia, the free encyclopedia.
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The end of the block or alternative block is marked by the #endif directive. similar to the combined use of the else-if statements in C. This directive delimits alternative source lines to be compiled Consider the following equivalent examples. #if is a preprocessor command, which gets evaluated before the actual compilation step. . For example, on Visual C++ the switch /P command will execute the C and C++ but there is no language called C/C++ and it's not a good habit to. The C Preprocessor: Elif. Elif. One common case of nested conditionals is used to check for more than two possible alternatives. For example, you might have group and subdivides it; it does not require a matching ' #endif ' of its own. The C preprocessor is a macro preprocessor (allows you to define macros) that In C programming, you can instruct preprocessor whether to include certain chuck of codes if expression is non-zero #else conditional if expression is 0 # endif. No semicolon (;) is expected at the end of a preprocessor directive. many occasions different from the normal expressions programmers expect in C++. Conditional inclusions (#ifdef, #ifndef, #if, #endif, #else and #elif) This example aborts the compilation process if the macro name __cplusplus is not.
this If endif c example s
Description. In the C Programming Language, the #endif directive closes off the following directives: #if, #ifdef, or #ifndef. When the #endif directive is encountered. Macro replacement is done within the part of the line that follows an #elif In the following example, the #if and #endif directives control. No semicolon (;) is expected at the end of a preprocessor directive. C provides the following preprocessor directives: The #define Preprocessor Directive as. #if - Test if a compile time condition is true. #else - The alternative for #if. #elif - #else an #if in one statement. #endif. The end of the block or alternative block is marked by the #endif directive. similar to the combined use of the else-if statements in C. This directive delimits alternative source lines to be compiled Consider the following equivalent examples. Debug is ON Hi friends! In this example macro DEBUG is defined so code written within the #ifdef and #else will be executed. If macro DEBUG was not defined. Learn #if, #elif, #else, #endif Pre-processor with Example in c programming #elif LANGUAGE==ENG_UK printf("Selected language is: ENG_UK\n"); #else. In case of #ifndef, the block of statements between #ifndef and #endif will be executed only if the macro or the identifier with #ifndef is not defined. The #ifdef, #ifndef, #elseif, #elif, #else, and #endif are the logical directives of the #elif NameN lines to evaluate if NameN is defined, and Name0-Name(N-1) is Not The following sample code showing use of the #ifdef directive chain with.Conditional Compilation (#if, #ifdef, #ifndef, #else, #elif, #endif, and defined). Six directives are available to control conditional compilation. They delimit blocks of program text that are compiled only if a specified condition is true.