No, the compiler does nothing with those characters. Anything past the first null is considered non-data, or garbage. There is still the problem of giving an existing character array a value. That is, suppose you have a character array, mystring. It is important to know that these built-in functions will automatically put the null character in the array at the end of the data. This is true for strcpy and strcat.
But you must always be aware of the size of your arrays! Similar to strcpy , strcat will return nothing, but takes two ntcas, the first non-const and the second const. It will concatenate the second source onto the first target. Pitfall: even worse than that of strcpy , walking off the array is very easy to do. Now target is. The strcmp function is a bit different. The information it gives you will also depend on the compiler and the platform you are working on.
I will tell you about our GNU compiler on our system. The GNU compiler will compare the two strings passed to the function lexicographically. That is, each character of the first parameter is compared to each character of the second parameter until a difference is encountered or a null character is reached. Thus, the function first compares ntca1[0] to ntca2[0].
It compares ntca1[1] to ntca2[1]. This continues until a difference if found. Suppose that a difference is found in the nth index.
If the opposite is the case, then 1 is returned. Notice that you have to negate the logic of the if condition since 0 false is returned when the ntcas are identical.
These functions will allow the user to walk off the array. You must keep track of the size of the arrays you are working with and the size of the data you wish to store in them. There are other versions of 3 of these.
They are strncpy , strncmp , and strncat. They all have an additional parameter of type int representing the number of characters you wish to copy, concatenate, or compare. They are touted as being safer. OK Paste as. Treat my content as plain text, not as HTML. Existing Members Sign in to your account.
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Let's work to help developers, not make them feel stupid. Related Questions. Checking for a character in array with an if sentence in C. How to print first and last character of a string in C? What does missing terminating " character mean?
Is this what you expected? For a standard C string the length of the array that is storing the string is always one character longer then the length of the string in characters. So your "hello world" string has a string length of 11 but requires a backing array with 12 entries.
The reason for this is simply the way those string are read. If this character is missing those functions just keep reading the memory until they either hit a protected memory area that causes the host operating system to kill your application or until they find the termination character.
Also if you initialize a character array with the length 11 and write the string "hello world" into it will yield massive problems. Because the array is expected to hold at least 12 characters. That means the byte that follows the array in the memory is overwritten. Resulting in unpredictable side effects.
It might be worth looking into that. In your case:. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 9 years, 9 months ago. Active 8 years, 7 months ago. Viewed 48k times. John Mahoney John Mahoney 1 1 gold badge 1 1 silver badge 6 6 bronze badges.
Since you are learning, it is important that you know from the beginning the names of the things you are learning. The literal itself is an array of constant characters with a null terminator, but the variable you have defined is a pointer. Add a comment. Active Oldest Votes. JaredPar JaredPar k gold badges silver badges bronze badges.
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