blob: a89414d098bbd14d05372db5c889e316a25f43c5 [file] [log] [blame]
// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
package os
import "syscall"
// Some systems set an artificially low soft limit on open file count, for compatibility
// with code that uses select and its hard-coded maximum file descriptor
// (limited by the size of fd_set).
// Go does not use select, so it should not be subject to these limits.
// On some systems the limit is 256, which is very easy to run into,
// even in simple programs like gofmt when they parallelize walking
// a file tree.
// After a long discussion on, we decided the
// best approach was for Go to raise the limit unconditionally for itself,
// and then leave old software to set the limit back as needed.
// Code that really wants Go to leave the limit alone can set the hard limit,
// which Go of course has no choice but to respect.
func init() {
var lim syscall.Rlimit
if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &lim); err == nil && lim.Cur != lim.Max {
lim.Cur = lim.Max
syscall.Setrlimit(syscall.RLIMIT_NOFILE, &lim)