Fix unused result

[hellerve]

This PR fixes #11. It introduces the helper function write_wrapped to ignore warnings on certain versions of GCC/glibc and unused results.

[kianmeng]

Disclaimer: I'm not a C programmer in what so ever way. ;-)
Wouldn't be nice to check for return value of write and name the function following your naming convention of e_foobar?

void e_write(int file, const char* str, int len) {
    if (write(file, str, len) != len) {
        fprintf(stderr, "Cannot write to file %i with error: %s\n", file, strerror(errno));
    }
}

[hellerve]

I understand your concern here. A lot of the time in C we don’t do all of the error checking we could do because we assume that some calls never fail—in e I also don’t check for failures of malloc/realloc for instance. I’m also not so sure about fprintfing the error here, especially after the last call to write failed and considering that the user could redirect stderr, leading to weird artifacts on the screen (in the best case).

As per the naming convention: the e_<function> convention is only really important for exported functions (as in, functions that are in the header) I feel, but I would agree that it’s less of a code smell to follow it regardless. I shall update it in the next commit.