From: "William E. Kempf" <[EMAIL PROTECTED]> > > OK, I've been looking at boost::filesystem_error. Here's my thoughts: > > boost::filesystem_error could be benefited by splitting it up into more > exception types. I know this was suggested in the review, but don't know > what the plan was in regard to this. In Boost.Threads case, so far we have > need for 4 different errors: lock errors, resource errors, invalid arguments and > unsupported errors.
POSIX actually distinguishes out of memory errors (ENOMEM) from other lack of resource errors (EAGAIN), and POSIX functions can fail with an "access denied" error (EPERM). There are also several types of POSIX lock errors (EINVAL, EBUSY, EAGAIN, EDEADLK, EPERM.) Boost.Threads has two additional lock errors associated with the Lock concept that have no POSIX equivalent. > Some have suggested carrying the OS error code, but given only 4 possible error > conditions, does this even sound reasonable? If the reason for the failure can be identified by the type of the exception, there should be no immediate need to carry an OS error code, although you should consider the "how do I translate this to a localized error message" problem. > Or are people > suggesting Boost.Threads should use a single exception type and carry the error > code, as filesystem_error currently does? No, this would be a step backward. IIUC filesystem_error is expected to evolve into a hierarchy as exception categories of interest to callers are identified. _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
