C strcat() Function

Posted in C Tutorial

Updated on Jan 14, 2024

By Mari Selvan

👁️ 180 - Views

⏳ 4 mins

💬 1 Comment

Photo Credit to CodeToFun

🙋 Introduction

In C programming, working with strings is a common and fundamental task.

The strcat() function, short for "string concatenate," is a standard library function that allows you to concatenate (append) one string to another.

In this tutorial, we'll explore the usage and functionality of the strcat() function in C.

💡 Syntax

The signature of the strcat() function is as follows:

Syntax

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char *strcat(char *dest, const char *src);

This function takes two arguments: dest, which is the destination string (the string to which the source string will be appended), and src, the source string (the string that will be appended to the destination).

📄 Example

Let's delve into an example to illustrate how the strcat() function works.

strcat.c

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#include <stdio.h>
#include <string.h>

int main() {
  char destination[20] = "Hello, ";
  const char * source = "World!";

  // Concatenate strings
  strcat(destination, source);

  // Output the result
  printf("Concatenated String: %s\n", destination);

  return 0;
}

💻 Output

Output

Concatenated String: Hello, World!

🧠 How the Program Works

In this example, the strcat() function appends the string "World!" to the existing string "Hello, " in the destination array.

↩️ Return Value

The strcat() function returns a pointer to the destination string (dest). It is essential to note that the resulting concatenated string is stored in the destination string itself.

📚 Common Use Cases

The strcat() function is particularly useful when you need to combine two strings to create a single, longer string. It is commonly used in scenarios where you want to build strings dynamically during runtime.

📝 Notes

Ensure that the destination string (dest) has sufficient space to accommodate the concatenated result. Overlapping strings should be avoided.
The strcat() function does not perform boundary checking, and care must be taken to avoid buffer overflow.

🎢 Optimization

While the strcat() function is a standard and efficient way to concatenate strings, consider using safer alternatives like strncat() if you need to control the number of characters appended or if you want to ensure null-termination in all cases.

🎉 Conclusion

The strcat() function in C is a powerful tool for string concatenation. It simplifies the process of combining strings, making it easier to manipulate and construct dynamic strings in your programs.

Feel free to experiment with different strings and explore the behavior of the strcat() function in various scenarios. Happy coding!