Which function is used to calculate the length of a string in C?

Which function is used to calculate the length of a string in C?

• A. strsize()
• B. strlen()
• C. lengthof()
• D. strcount()

Answer: (B)

The function used to calculate the length of a string in C is `strlen()`. This function is part of the standard C library, specifically included in the `<string.h>` header file. When called, `strlen()` takes a string (character array) as an argument and returns the number of characters in that string, excluding the null terminator (`\0`) that marks the end of the string. For example, if you have a string defined as `char str[] = "Hello";`, calling `strlen(str)` would return 5, since there are five characters in "Hello". It is important to understand that `strlen()` counts only the characters and not the null character, which is crucial for proper string manipulation in C. The other options do not correspond to any standard C library functions for calculating string lengths. This makes `strlen()` the only correct function in the context of obtaining the length of a string in C programming.

The function used to calculate the length of a string in C is strlen(). This function is part of the standard C library, specifically included in the <string.h> header file. When called, strlen() takes a string (character array) as an argument and returns the number of characters in that string, excluding the null terminator (\0) that marks the end of the string.

For example, if you have a string defined as char str[] = "Hello";, calling strlen(str) would return 5, since there are five characters in "Hello". It is important to understand that strlen() counts only the characters and not the null character, which is crucial for proper string manipulation in C.

The other options do not correspond to any standard C library functions for calculating string lengths. This makes strlen() the only correct function in the context of obtaining the length of a string in C programming.