What I am trying to do is implement a associative array to lookup data
based on a key in C. This might simple to do in C++ or Perl but I'm
restricted to use C. The size of the data for the table isn't too
large but too large to structure the code as a clean chain of if/else
or similar logic. Also, the lookup key values can be large,
unpredictable and not well dispersed which doesn't suit itself to a
hash table.
OK so my current idea for implementing this is using an array of C
structures which gets initialized and contains all the relevant
information. The array will be a module global variable used in the C
file which needs this functionality. The array definition would look
something like the following:
struct ErrorLookupTable
{
long DeviceErrorCode;
char* ErrorString;
};
#define TableSize 6
static struct ErrorLookupTable MyTable[ TableSize ] =
{
{ 45, "Not enough memory" },
{ -66, "File I/O error" },
{ -2565, "Device locked" },
{ 32727, "Device not found" },
{ -32727, "Device not found" },
{ 65534, "Unknown device error" }
//... LOTS more
};
So I have implemented some prototype code based on this and it does
work to do lookups. But what I was wondering is how ****table is
this? Is this legal C as defined by the standard to initialize an
array of structures in this way? Is this going to work across
platforms? I hope you see my dilemma the code appears to work on my
system. But I don't know if it's guaranteed to work everywhere and how
****table the library functions I'm working on will be because of it?
Thanks. :)
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