handle possible failure of fstat

[drbitboy]

ImageStreamIO/ImageStreamIO.c

Line 1312 in d6f9c28

fstat(SM_fd, &file_stat);

Should we ignore failure of that fstat call?

From man fstat(2), the only reasons it could fail in this context is if the kernel was out of memory, or it is called on a 32-bit architecture with a file bigger than 2GB or 4Gb, so I don't see this as an urgent issue.