Dave Chinner wrote: Thanks for asking for clarification. > On Sat, Jun 18, 2016 at 04:52:38PM +0200, Felix Janda wrote: > > The off64_t type is usually only conditionally exposed under the > > feature test macro _LARGEFILE64_SOURCE (also defined by _GNU_SOURCE). > > To make the public xfs headers more standalone therefore off64_t should > > be avoided. > > "more standalone"? > > What does that mean? Programs including the xfs headers while not defining _GNU_SOURCE or _LARGEFILE64_SOURCE will not fail with compile errors. My previous patch changing loff_t to off64_t had the unintented consequences that downstreams of xfs-progs like ceph had to define _LARGEFILE64_SOURCE on linux. > And what does it mean for all the xfsprogs code that still uses > off64_t? off_t and off64_t are now synomyms and 64 bit on all architectures. So no difference for code using off64_t. Under some conditions there can be a difference for code using off_t. > i.e. if you are going to make xfsprogs fail to compile on configs > that don't define off64_t, then it makes no sense to leave all the > users of off64_t in the xfsprogs code.... On all supported systems except for current default linux (glibc) configurations either there does not exist off64_t or it is the same as off_t. The configure test will define _FILE_OFFSET_BITS=64 on linux systems (i.e. enabling transparent large file support) with the result that now even on linux off_t is 64 bit wide in all cases. The "assert" ensures that programs using the xfs headers do not compile when the expectation sizeof(off_t)=8 is not met. This makes programs on 32 bit linux systems using the xfs headers but not defining _FILE_OFFSET_BITS=64 not compile. I would consider this as beneficial because such programs easily can have bugs regarding support of files of size >2GB on 32 bit systems. Felix _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
