open-nomad/vendor/github.com/opencontainers/selinux/pkg/pwalk/README.md

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## pwalk: parallel implementation of filepath.Walk
This is a wrapper for [filepath.Walk](https://pkg.go.dev/path/filepath?tab=doc#Walk)
which may speed it up by calling multiple callback functions (WalkFunc) in parallel,
utilizing goroutines.
By default, it utilizes 2\*runtime.NumCPU() goroutines for callbacks.
This can be changed by using WalkN function which has the additional
parameter, specifying the number of goroutines (concurrency).
### Caveats
Please note the following limitations of this code:
* Unlike filepath.Walk, the order of calls is non-deterministic;
* Only primitive error handling is supported:
* filepath.SkipDir is not supported;
* no errors are ever passed to WalkFunc;
* once any error is returned from any WalkFunc instance, no more new calls
to WalkFunc are made, and the error is returned to the caller of Walk;
* if more than one walkFunc instance will return an error, only one
of such errors will be propagated and returned by Walk, others
will be silently discarded.
### Documentation
For the official documentation, see
https://pkg.go.dev/github.com/opencontainers/selinux/pkg/pwalk?tab=doc
### Benchmarks
For a WalkFunc that consists solely of the return statement, this
implementation is about 10% slower than the standard library's
filepath.Walk.
Otherwise (if a WalkFunc is doing something) this is usually faster,
except when the WalkN(..., 1) is used.