# README

go-where

A library for determining the root path of an executable. Supported on Windows, macOS, and Linux.

Breaking changes in v2.0.0 The library has been simplified to a single exported function that accepts a configuration object. All of the prior capabilities are supported, but there are no longer inidivdual functions for finding one path vs multiple paths, exceptions, etc.

myapp.go:

package main

import (
  "fmt"
  "os"
  "github.com/coreybutler/go-where/v2"
)

func main() {
  executable := os.Args[1]
  path, err := where.Find(executable)

  if err != nil {
    panic(err)
  }

  fmt.Print(path[0])
}

Run this with:

$ go run myapp.go node.exe
C:\nodejs\node.exe

Confguration Options

The Options type is defined as:

type Options struct {
	All       bool     `json:"all"`
	Recursive bool     `json:"recursive"`
	Except    []string `json:"except"`
}

Option	Description	Default
All	Return all paths where the executable is found (as opposed to the first one)	`false`
Recursive	Search `PATH` directories recursively for the executable.	`true`
Except	A slice of paths/glob patterns to ignore. Ths can be used to override specific file types, such as ignoring `.bat` files on Windows	`[]string{}` (empty slice)

package main

import (
  "fmt"
  "os"
  "github.com/coreybutler/go-where/v2"
)

func main() {
  executable := os.Args[1]
  // The boolean argument indicates a recursive lookup
  path, err := where.Find(executable, where.Options{
    Except: []string{"C:\nodejs\node.exe"}
  })

  if err != nil {
    panic(err)
  }

  fmt.Print(path[0])
}

$ go run myapp.go node.exe
not found
# C:\nodejs\node.exe was ignored!

File Extensions

It is best to supply the file extension of the executable, but this library will attempt to identify executables in three ways:

By bit On some operating systems, the first byte(s) of the file flag whether it is executable or not.

By file permissions If the file has explicit execute permissions, it will be considered "executable".

By file extension File extensions are used as a last resort.

For example:

fmt.Print(where.Find("node"))
// C:\nodejs\node.exe

File extension identification is limited to a hard-coded list of known extensions. See the files named expand_*.go.