v2: remove errors that are never returned

thaJeztah · thaJeztah · commit b19a60d64d89 · 2021-07-15T11:14:18.000+02:00
Unlike v1, the v2 package never returns these errors. This patch removes
them to prevent consumers of this package from assuming they may be returned,
and writing special handling around them.

NOTE: this is a breaking change, so (following SemVer) would require a major
version update. However, consumers should not use these errors. Alternatively,
we could "deprecate" them first. Making it a breaking change makes it more
visible (compile time error), which may help consumers to find incorrect
handling of these errors.

Signed-off-by: Sebastiaan van Stijn &lt;github@gone.nl&gt;
diff --git a/v2/errors.go b/v2/errors.go
@@ -22,16 +22,8 @@ import (
 )
 
 var (
-	ErrInvalidPid               = errors.New("cgroups: pid must be greater than 0")
-	ErrMountPointNotExist       = errors.New("cgroups: cgroup mountpoint does not exist")
-	ErrInvalidFormat            = errors.New("cgroups: parsing file with invalid format failed")
-	ErrFreezerNotSupported      = errors.New("cgroups: freezer cgroup (v2) not supported on this system")
-	ErrMemoryNotSupported       = errors.New("cgroups: memory cgroup (v2) not supported on this system")
-	ErrPidsNotSupported         = errors.New("cgroups: pids cgroup (v2) not supported on this system")
-	ErrCPUNotSupported          = errors.New("cgroups: cpu cgroup (v2) not supported on this system")
-	ErrCgroupDeleted            = errors.New("cgroups: cgroup deleted")
-	ErrNoCgroupMountDestination = errors.New("cgroups: cannot find cgroup mount destination")
-	ErrInvalidGroupPath         = errors.New("cgroups: invalid group path")
+	ErrInvalidFormat    = errors.New("cgroups: parsing file with invalid format failed")
+	ErrInvalidGroupPath = errors.New("cgroups: invalid group path")
 )
 
 // ErrorHandler is a function that handles and acts on errors
