wanted: `open(create=true, exclusive=true)` dead or alive

[vtjnash]

Sometimes useful, for creating atomic lockfiles (https://github.com/vtjnash/Pidfile.jl) or secure tempfiles:

julia/base/file.jl

Line 586 in 31bf76f

`JL_O_EXCL` if this is a concern. Using [`mktemp()`](@ref) is also

The exclusive=true flag (only valid in combination with create=true) should simply map the the underlying O_EXCL option to open (this exists everywhere that Julia runs).

(could also try to add O_NOFOLLOW, though FILE_FLAG_OPEN_REPARSE_POINT is more like O_SYMLINK, and so is hard to implement everywhere. And there's a couple others like RANDOM, SEQUENTIAL, SYNC, DSYNC, NOATIME, DIRECT, and SHORT_LIVED that could even be filtered out when not supported.)

[aaryan20]

Hello! Can I work on this Issue?

[KristofferC]

Anyone can work on any issue. There is no need to go around asking for permission on a bunch of issues, it just creates a bunch of notifications.