Dynamicstring length determination

[PhilG57]

How do I determine the length of an "embedded" character string?  I would like to code a strncpy in which the length field (??? in the example below) would be determined during compilation.  Is there some way to reference the "...." characters with a 'sizeof' or 'strlen' call so I can get its length?   

strncpy(ToLocation, "some characters here", ???);

Thanks.

[CommonTater]

How do I determine the length of an "embedded" character string?  I would like to code a strncpy in which the length field ( in the example below) would be determined during compilation.  Is there some way to reference the "...." characters with a 'sizeof' or 'strlen' call so I can get its length?   

strncpy(ToLocation, "some characters here", );

Thanks.

Like this...

Code: [Select]

strncpy(To, "This is a test!",strlen("This is a test!");

However; strncpy() isn't needed with string constants so long as you know the buffer is big enough, since they're guaranteed to be 0 terminated. 
 
If you're copying to a buffer that may be smaller than your text, use the buffer's size in strncpy()
For example:

Code: [Select]

#define BUF_SIZE 16;
 
// in active code
char buf[BUF_SIZE + 1] = {0};  //extra character for trailing 0;
 
strncpy(buf, "This is going to be longer than the buffer",BUF_SIZE);
This avoids buffer overflow problems but will completely copy shorter strings.
 

[PhilG57]

Got it - strlen of the same character string.  Pretty cool, actually.  Thanks - again.

[CommonTater]

Got it - strlen of the same character string.  Pretty cool, actually.  Thanks - again.

The most appopriate use is the second one where you use the size of the text buffer itself.

Glad to help.