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package foldmain
import (
"io"
"net"
"os"
"path/filepath"
)
type Invocation struct {
Args []string
Getenv func(string) string
Stdout io.Writer
Stderr io.Writer
Exe string
Verb []string
Listen func(name string, addr net.Addr)
}
func OS() Invocation {
exe, _ := ResolveExe()
return Invocation{Args: os.Args[1:], Getenv: os.Getenv, Stdout: os.Stdout, Stderr: os.Stderr, Exe: exe}
}
func ResolveExe() (string, error) {
p, err := os.Executable()
if err != nil {
return "", err
}
return Resolve(p)
}
func Resolve(p string) (string, error) {
abs, err := filepath.Abs(p)
if err != nil {
return "", err
}
return filepath.EvalSymlinks(abs)
}
func (i Invocation) MultiCall() bool { return len(i.Verb) > 0 }
func (i Invocation) Self() []string {
return append([]string{i.Exe}, i.Verb...)
}
func (i Invocation) Reexec(verb ...string) []string {
if !i.MultiCall() || i.Exe == "" {
return nil
}
return append([]string{i.Exe}, verb...)
}
func (i Invocation) Env(name string) string {
if i.Getenv == nil {
return ""
}
return i.Getenv(name)
}
func (i Invocation) Listened(name string, addr net.Addr) {
if i.Listen != nil {
i.Listen(name, addr)
}
}
