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// Copyright 2012 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.
package runtime
import "unsafe"
func getenv(s *byte) *byte {
val := gogetenv(gostringnocopy(s))
if val == "" {
return nil
}
// Strings found in environment are NUL-terminated.
return &bytes(val)[0]
}
var tracebackbuf [128]byte
func gogetenv(key string) string {
var file [128]byte
if len(key) > len(file)-6 {
return ""
}
copy(file[:], "/env/")
copy(file[5:], key)
fd := open(&file[0], _OREAD, 0)
if fd < 0 {
return ""
}
n := seek(fd, 0, 2)
if n <= 0 {
close(fd)
return ""
}
p := make([]byte, n)
r := pread(fd, unsafe.Pointer(&p[0]), int32(n), 0)
close(fd)
if r < 0 {
return ""
}
if p[r-1] == 0 {
r--
}
var s string
sp := (*_string)(unsafe.Pointer(&s))
sp.str = &p[0]
sp.len = int(r)
return s
}
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