Question

I am trying to use a timer library that I created my self, it uses clock_t in it. When I compile the sketch i keep getting errors. This is the error I keep getting error: 'clock_t' in namespace 'std' does not name a type.

Is it even possible to use clock_t. The library I wrote worked perfectly on a c++ compiler, but not here.

I am new to this Arduino stuff, any help will be nice. Thanks in advance.

Answer 1

Arduino links against AVR Libc, and most of the things that look similar to C standard library come from it.

As far as I know, there is no clock_t in AVR Libc. I searched among the source files of the library, and looked around the documentations, but didn’t find it. There is no time.h in AVR Libc, either.

And according to Arduino FAQ:

…the Arduino language is merely a set of C/C++ functions that can be called from your code. Your sketch undergoes minor changes (e.g. automatic generation of function prototypes) and then is passed directly to a C/C++ compiler (avr-g++). All standard C and C++ constructs supported by avr-g++ should work in Arduino. …

And in AVR-libc FAQ:

Can I use C++ on the AVR?

However, there’s currently no support for libstdc++, the standard support library needed for a complete C++ implementation. This imposes a number of restrictions on the C++ programs that can be compiled. Among them are:

• Obviously, none of the C++ related standard functions, classes, and template classes are available.

So, Arduino doesn’t provide C++ standard library for you – so ctime (C++) is not available as well as time.h (C). That’s to say, most likely you cannot use clock_t in Arduino environment.