Actually that code would have to read unsigned char your_bytes[4] = 43BE1959; unsigned long your_integer = *((unsigned long *) your_bytes);
to really mean anything. But in the end this is why we provide open source libraries for this stuff - it's no fun to constantly reimplement and debug. On Fri, Feb 4, 2011 at 10:57 AM, Natalie Tasman <[email protected]> wrote: > Nice job on tracking that down. I'm sure there are other examples but > in TPP's src/mzXML/common directory you can look at the Base64 and > ScanConverter.cpp for code examples and some documentation on the > encoding. > > -Natalie > > On Fri, Feb 4, 2011 at 6:56 AM, dre <[email protected]> wrote: >> Actually I think I figured it out....in case anyone else out there is >> wondering - if you have a c-style char array holding your hex value, >> it will be automatically converted to the host endianess when type >> casting into an integer. So then the bytes have to be reconverted >> again (network to host) before used. This was a little bit hard to see >> at first but now it seems to make sense. ex: >> >> unsigned char your_bytes[4] = 43BE1959; >> unsigned long your_integer = (unsigned long) your_bytes; >> >> //this will give 2.70467 E15 which is at first unintuitive, but if you >> consider that when casting a char to an int your getting an endianness >> change it makes sense >> >> so instead >> >> unsigned long you_integer = ntoh ((unsigned long) your_bytes); >> >> //this will then give the true value of 380.19 >> >> -- >> You received this message because you are subscribed to the Google Groups >> "spctools-discuss" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]. >> For more options, visit this group at >> http://groups.google.com/group/spctools-discuss?hl=en. >> >> > > -- > You received this message because you are subscribed to the Google Groups > "spctools-discuss" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/spctools-discuss?hl=en. > > -- You received this message because you are subscribed to the Google Groups "spctools-discuss" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/spctools-discuss?hl=en.
