C Articles - Page 121 of 134

In this section we will see how to convert a number (integer or float or any other numeric type data) to a string.The logic is very simple. Here we will use the sprintf() function. This function is used to print some value or line into a string, but not in the console. This is the only difference between printf() and sprintf(). Here the first argument is the string buffer. where we want to save our data.Input: User will put some numeric value say 42.26 Output: This program will return the string equivalent result of that number like "42.26"AlgorithmStep 1: Take ... Read More

In this post you can get some details where you can buy and view free drafts of some current and past C/C++ standards.C DocumentsC11:198 CHF (https://www.iso.org/standard/57853.html)Publicly at (http://www.open-std.org/JTC1/SC22/WG14/www/docs/n1570.pdf)Wikipedia Link (https://en.wikipedia.org/wiki/C11_(C_standard_revision))C99:Cannot Purchase (https://www.iso.org/standard/29237.html)Publicly at (http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf)Wikipedia Link (https://en.wikipedia.org/wiki/C99)C90, C89, ANSI C, Standard CWikipedia Page: (https://en.wikipedia.org/wiki/ANSI_C)C++ DocumentsC++14:198 CHF (https://www.iso.org/standard/64029.html)Based On (https://www.iso.org/standard/29237.html)Wikipedia Link (https://en.wikipedia.org/wiki/ANSI_C)C++11:Cannot Purchase (https://www.iso.org/standard/50372.html)Publicly at (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf)Wikipedia Link (https://en.wikipedia.org/wiki/C%2B%2B11)C++03Wikipedia Page: (https://en.wikipedia.org/wiki/C%2B%2B03)C++89Wikipedia Page: (https://en.wikipedia.org/wiki/C%2B%2B)Read More

A forward declaration informs the compiler that a class, function, or variable is declared earlier, but it will be defined later in the code. In this article, our task is to understand the forward declaration and when to use it. When is Forward Declaration Used in C/C++? The forward declaration can be used in C/C++ in the following cases: In C++, it is used for declaring a friend function. Using the forward declaration, we can reduce the header files that we include in the code. When ... Read More

The size of a struct type element taken by sizeof() is not always equal to the size of each individual member. Sometimes the compilers add some padding to avoid alignment issues. So the size may change. The padding is added when a structure member is followed by a member with a larger size or at the end of the structure. Different compiler has different types of alignment constraints. In C standard, the total alignment structure depends on the implementation.Case 1In this case the double z is 8-byte long, which is larger than x (4-byte). So another 4-byte padding is added. ... Read More

In this section we will see how to see the Host name and IP address of the local system in an easier way. We will write a C program to find the host name and IP.Some of the following functions are used. These functions have different task. Let us see the functions and their tasks.FunctionDescriptiongethostname()It finds the standard host name for the local computer.gethostbyname()It finds the host information corresponding to a host name from host databaseiten_ntoa()It converts an IPv4 Internet network address into an ASCII string into dotted decimal format.Example Code#include #include #include #include #include ... Read More

Here we will see how to generate hollow pyramid and diamond patterns using C. We can generate solid Pyramid patterns very easily. To make it hollow, we have to add some few tricks.Hollow PyramidFor the pyramid at the first line it will print one star, and at the last line it will print n number of stars. For other lines it will print exactly two stars at the start and end of the line, and there will be some blank spaces between these two starts.Example Code#include int main() {    int n, i, j;    printf("Enter number of lines: ... Read More

In this section we will see how to make a digital clock using C. To work with time we can use the time.h header file. This header file has some function signatures that are used to handle date and time related issues.The four important components of time.h is like belowsize_t This size_t is basically the unsigned integral type. This is the result of sizeof().clock_t This is used to store the processor timetime_t This is used to store calendar timestruct tm This is a structure. It helps to hold the entire date and time.Example Code#include #include int main() { ... Read More

The PGM is the Portable Gray Map. If we want to store a 2d array in C as images in PNG, JPEG, or any other image format, we have to do lots of work to encode the data in some specified format before writing into a file.The Netpbm format gives an easy and portable solution. The Netpbm is an open source package of graphics program and it is used basically in linux or Unix platform. It also works under Microsoft Windows systems.Each file starts with a two-byte magic number. This magic number is used to identify the type of the ... Read More

In this program we will see how to validate an IP address using C. The IPv4 addresses are represented in dot-decimal notation. There are four decimal numbers (all are ranging from 0 to 255). These four numbers are separated by three dots.An example of a valid IP is: 192.168.4.1To validate the IP address we should follow these stepsTokenize the string (IP address) using the dot “.” delimiterIf the sub strings are containing any non-numeric character, then return falseIf the number in each token is not in range 0 to 255, then return falseIf there are exactly three dots and four ... Read More

In this article we will see how we can print some characters without using any kind of format specifiers. The format specifiers in C are %d, %f, %c etc.These are used to print characters and numbers in C using the printf() function.Here we will see another way to print characters without using %c format specifier. This can be done by putting ASCII values directly in hexadecimal form.Example Code#include main () { printf("\x41 "); //41 is ASCII of A in Hex printf("\x52 "); //41 is ASCII of A in Hex printf("\x69 ... Read More