Don't attempt to set file descriptor limit.

Recent versions of Go do it at startup, so only print
a warning if the limit is too low.

galene.go

@@ -104,9 +104,9 @@ func main() {
 		}()
 	}
 
-	n, err := limit.Nofile(0xFFFF)
+	n, err := limit.Nofile()
 	if err != nil {
-		log.Printf("Couldn't set file descriptor limit: %v", err)
+		log.Printf("Couldn't get file descriptor limit: %v", err)
 	} else if n < 0xFFFF {
 		log.Printf("File descriptor limit is %v, please increase it!", n)
 	}

limit/limit.go

@@ -1,7 +1,7 @@
-// +build !linux
+//go:build !unix
 
 package limit
 
-func Nofile(desired uint64) (uint64, error) {
-	return desired, nil
+func Nofile() (uint64, error) {
+	return 0xFFFF, nil
 }

limit/limit_unix.go

@@ -1,4 +1,4 @@
-// +build linux
+//go:build unix
 
 package limit
 
@@ -6,38 +6,13 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-func Nofile(desired uint64) (uint64, error) {
-	var old unix.Rlimit
+func Nofile() (uint64, error) {
+	var limit unix.Rlimit
 
-	err := unix.Getrlimit(unix.RLIMIT_NOFILE, &old)
+	err := unix.Getrlimit(unix.RLIMIT_NOFILE, &limit)
 	if err != nil {
 		return 0, err
 	}
 
-	if old.Cur >= desired {
-		return old.Cur, nil
-	}
-
-	if old.Max < desired {
-		limit := unix.Rlimit{
-			Cur: desired,
-			Max: desired,
-		}
-		err := unix.Setrlimit(unix.RLIMIT_NOFILE, &limit)
-		if err == nil {
-			return limit.Cur, nil
-		}
-
-		desired = old.Max
-	}
-
-	limit := unix.Rlimit{
-		Cur: desired,
-		Max: old.Max,
-	}
-	err = unix.Setrlimit(unix.RLIMIT_NOFILE, &limit)
-	if err != nil {
-		return old.Cur, err
-	}
-	return limit.Cur, nil
+	return uint64(limit.Cur), nil
 }