[boost] [iostreams] File times on POSIX systems

Hello, currently iostreams has a number of failures on POSIX systems because of the use of the non-existent function futimes(). futimes() conforms to 4.2BSD and is unknown to POSIX, which only has utime() to set file access and modification times. Unfortunately utime() works in term of path names and not file descriptors, and I'm not aware of any suitable replacement, so perhaps the interface for the functionality in question needs to be changed. Regards, Markus