x/sys/unix: missing Fgetxattr and Fsetxattr

[masiulaniec]

The system calls fgetxattr(2) and fsetxattr(2) are not exposed. These variants are required to avoid some path-based race conditions caused by concurrent rename(2) calls.

[FiloSottile]

/cc @ianlancetaylor @bradfitz @tklauser

[ianlancetaylor]

@masiulaniec Which operating system?

[tklauser]

FWIW, it seems to be missing on all operating systems except FreeBSD.

[gopherbot]

Change https://golang.org/cl/128176 mentions this issue: unix: add F*xattr on Linux

[masiulaniec]

@masiulaniec Which operating system?

I need it on Linux and Darwin. It might be applicable to other systems.

[gopherbot]

Change https://golang.org/cl/128495 mentions this issue: unix: drop incorrect Fsetxattr size return value

[gopherbot]

Change https://golang.org/cl/128537 mentions this issue: unix: add F*xattr on Darwin