I try to read binary file and it has section in following format:
(I suspect this comes from .h file)
...
then the bars array (one-byte justification) follows
pragma pack(push,1)
//---- Standard representation of a quote in the base
struct RateInfo {
time_t ctm; // current time in seconds
double open;
double low;
double high;
double close;
double vol;
};
pragma pack(pop)
...
I don't know what to do with pragma pack. I googled and found that this
is some weird bit-level alignment for records. But I can't figure out,
how do I read and .unpack such records.
Can I just do .read(4 + 5 * 8) and get a record?
How do I decode it if its packed with this pragma pack?
On 07/12/06, Leo -- <leopardus.vulgaris@gmail.com> wrote:
Hello everyone
I try to read binary file and it has section in following format:
(I suspect this comes from .h file)
...
then the bars array (one-byte justification) follows
pragma pack(push,1)
//---- Standard representation of a quote in the base
struct RateInfo {
time_t ctm; // current time in seconds
double open;
double low;
double high;
double close;
double vol;
};
pragma pack(pop)
...
I don't know what to do with pragma pack. I googled and found that this
is some weird bit-level alignment for records. But I can't figure out,
how do I read and .unpack such records.
Can I just do .read(4 + 5 * 8) and get a record?
How do I decode it if its packed with this pragma pack?
Yes, but I do not know how to apply it in the case of packed data
structure. I'm not much into CS, so if this is possible with
String#unpack I will be very happy if you can help me with format string
to unpack this "pragma pack(1)" data structure.
This is just a guess and I'm not sure what time_t is but if we assuume
it's an unsigned int then you could say:
ctm,open,low,high,close,vol = packedData.unpack("Iddddd")
Farrel
···
On 07/12/06, Leo -- <leopardus.vulgaris@gmail.com> wrote:
Farrel Lifson wrote:
> Have you looked at String#unpack ?
Yes, but I do not know how to apply it in the case of packed data
structure. I'm not much into CS, so if this is possible with
String#unpack I will be very happy if you can help me with format string
to unpack this "pragma pack(1)" data structure.