1 // Copyright 2009 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
5 //go:build unix && !ios && !android
7 // Parse "zoneinfo" time zone file.
8 // This is a fairly standard file format used on OS X, Linux, BSD, Sun, and others.
9 // See tzfile(5), https://en.wikipedia.org/wiki/Zoneinfo,
10 // and ftp://munnari.oz.au/pub/oldtz/
18 // Many systems use /usr/share/zoneinfo, Solaris 2 has
19 // /usr/share/lib/zoneinfo, IRIX 6 has /usr/lib/locale/TZ,
20 // NixOS has /etc/zoneinfo.
21 var platformZoneSources = []string{
22 "/usr/share/zoneinfo/",
23 "/usr/share/lib/zoneinfo/",
24 "/usr/lib/locale/TZ/",
29 // consult $TZ to find the time zone to use.
30 // no $TZ means use the system default /etc/localtime.
31 // $TZ="" means use UTC.
32 // $TZ="foo" or $TZ=":foo" if foo is an absolute path, then the file pointed
33 // by foo will be used to initialize timezone; otherwise, file
34 // /usr/share/zoneinfo/foo will be used.
36 tz, ok := syscall.Getenv("TZ")
39 z, err := loadLocation("localtime", []string{"/etc"})
42 localLoc.name = "Local"
49 if tz != "" && tz[0] == '/' {
50 if z, err := loadLocation(tz, []string{""}); err == nil {
52 if tz == "/etc/localtime" {
53 localLoc.name = "Local"
59 } else if tz != "" && tz != "UTC" {
60 if z, err := loadLocation(tz, platformZoneSources); err == nil {