C Articles - Page 133 of 134

The compilation of a C++ program consists of three steps −Preprocessing − In simple terms, a C Preprocessor is just a text substitution tool and it instructs the compiler to do required pre-processing before the actual compilation. It handles preprocessing directives like #include, #define, etc.Compilation − The compilation takes place on the preprocessed files. The compiler parses the pure C++ source code and converts it into assembly code. This in turn calls the assembler that converts the assembly code to machine code(binary) as Object files. These Object files can refer to symbols that are not defined. The compiler won't give ... Read More

A segmentation fault occurs when your program attempts to access an area of memory that it is not allowed to access. In other words, when your program tries to access memory that is beyond the limits that the operating system allocated for your program.Seg faults are mostly caused by pointers that are −Used to being properly initialized.Used after the memory they point to has been reallocated or freed.Used in an indexed array where the index is outside of the array bounds.

A process dumps core when it is terminated by the operating system due to a fault in the program. The most typical reason this occurs is that the program accessed an invalid pointer value like NULL or some value out of its memory area. As part of that process, the operating system tries to write our information to a file to allow us to analyze what happened.This core can be used as follows to diagnose and debug our program −The core is dumped to the /proc/sys/kernel directory by default. To debug a core, the program must be compiled with the ... Read More

Standard C++ doesn't provide a way to do this. You could use the system command to initialize the ls command as follows −Example#include int main () {    char command[50] = "ls -l";    system(command);    return 0; }OutputThis will give the output −-rwxrwxrwx 1 root root  9728 Feb 25 20:51 a.out -rwxrwxrwx 1 root root   131 Feb 25 20:44 hello.cpp -rwxrwxrwx 1 root root   243 Sep  7 13:09 hello.py -rwxrwxrwx 1 root root 33198 Jan  7 11:42 hello.o drwxrwxrwx 0 root root   512 Oct  1 21:40 hydeout -rwxrwxrwx 1 root root    42 Oct 21 11:29 ... Read More

Variables can be declared in a switch statement. You'll just need to declare them and use them within a new scope in the switch statement. For example,Example#include using namespace std; int main() {    int i = 10;    switch(i) {       case 2:       //some code       break;       case 10:{          int x = 13;          cout

argc stands for argument count and argv stands for argument values. These are variables passed to the main function when it starts executing. When we run a program we can give arguments to that program like −$ ./a.out helloExampleHere hello is an argument to the executable. This can be accessed in your program. For example,#include using namespace std; int main(int argc, char** argv) {    cout

You need to use extern "C" in C++ when declaring a function that was implemented/compiled in C.Using extern "C" lets the compiler know that we want to use C naming and calling conventions. This causes the compiler to sort of entering C mode inside our C++ code. This is needed because C++ compilers mangle the names in their symbol table differently than C compilers and hence behave differently than C compilers.

Neither C++ (98) nor the new standard(C++0x or C++11) is fully compatible with C. C++ never was fully compatible with C.

Example#include #include void main() {    int i,j,a=0,b=1,n;    clrscr();    printf("****************OUTPUT*****************");    printf("enter the value of n : ");    scanf("%d",&n);    printf(" the required order is: " );    for(i=1;i

Step 1 − Install MinGW GCC or Cygwin GCCTo use Eclipse for C/C++ programming, you need a C/C++ compiler. On Windows, you could install either MinGW GCC or Cygwin GCC. Choose MinGW if you are not sure, because MinGW is lighter and easier to install, but has fewer features.MinGW GCCTo install MinGW, go to the MinGW homepage, www.mingw.org, and follow the link to the MinGW download page. Download the latest version of the MinGW installation program which should be named MinGW .exe.While installing MinGW, at a minimum, you must install gcc-core, gcc-g++, binutils, and the MinGW runtime, but you may ... Read More