Namespace: go.std.plugin

v1.0

Contents

• Summary
• Index
• Constants
• Variables
• Functions, Macros, and Special Forms
• Types

Summary

Provides a low-level interface to the plugin package.

Package plugin implements loading and symbol resolution of Go plugins.

A plugin is a Go main package with exported functions and variables that
has been built with:

go build -buildmode=plugin

When a plugin is first opened, the init functions of all packages not
already part of the program are called. The main function is not run.
A plugin is only initialized once, and cannot be closed.

Currently plugins are only supported on Linux, FreeBSD, and macOS.
Please report any issues.

Index

• *Plugin
• Open
• Plugin
• Symbol
• arrayOfPlugin
• arrayOfSymbol

Legend

Constant Variable Function Macro Special form Type GoVar Receiver/Method

Constants

Constants are variables with :const true in their metadata. Joker currently does not recognize them as special; as such, it allows redefining them or their values.

(None.)

Variables

(None.)

Functions, Macros, and Special Forms

• Open

  Function v1.0

  (Open path)
  

  Open opens a Go plugin.
  If a path has already been opened, then the existing *Plugin is returned.
  It is safe for concurrent use by multiple goroutines.
  
  Go input arguments: (path string)
  
  Go returns: (*Plugin, error)
  
  Joker input arguments: [^String path]
  
  Joker returns: [^*Plugin, ^Error]

Types

• *Plugin

  Concrete Type v1.0

  Plugin is a loaded Go plugin.
  

• Lookup

  Receiver for *Plugin v1.0

  ([symName])
  

  Lookup searches for a symbol named symName in plugin p.
  A symbol is any exported variable or function.
  It reports an error if the symbol is not found.
  It is safe for concurrent use by multiple goroutines.
  

• Plugin

  Concrete Type v1.0

  Plugin is a loaded Go plugin.
  

• Symbol

  Abstract Type v1.0

  A Symbol is a pointer to a variable or function.
  
  For example, a plugin defined as
  
  package main
  
  import "fmt"
  
  var V int
  
  func F() { fmt.Printf("Hello, number %d\n", V) }
  
  may be loaded with the Open function and then the exported package
  symbols V and F can be accessed
  
  p, err := plugin.Open("plugin_name.so")
  if err != nil {
  panic(err)
  }
  v, err := p.Lookup("V")
  if err != nil {
  panic(err)
  }
  f, err := p.Lookup("F")
  if err != nil {
  panic(err)
  }
  *v.(*int) = 7
  f.(func())() // prints "Hello, number 7"
  

• arrayOfPlugin

  Concrete Type v1.0

  Plugin is a loaded Go plugin.
  

• arrayOfSymbol

  Concrete Type v1.0

  A Symbol is a pointer to a variable or function.
  
  For example, a plugin defined as
  
  package main
  
  import "fmt"
  
  var V int
  
  func F() { fmt.Printf("Hello, number %d\n", V) }
  
  may be loaded with the Open function and then the exported package
  symbols V and F can be accessed
  
  p, err := plugin.Open("plugin_name.so")
  if err != nil {
  panic(err)
  }
  v, err := p.Lookup("V")
  if err != nil {
  panic(err)
  }
  f, err := p.Lookup("F")
  if err != nil {
  panic(err)
  }
  *v.(*int) = 7
  f.(func())() // prints "Hello, number 7"