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+envcfg [![Build Status](https://travis-ci.org/Pacien/envcfg.svg)](//travis-ci.org/Pacien/envcfg)
+======
+
+Package [envcfg](//github.com/Pacien/envcfg) provides environment variable mapping to structs.
+
+It can be used to read configuration parameters from the environment.
+
+Fields for which environment variables can be found are overwritten, otherwise they are left to their previous value.
+
+This package can be used, for example, after [gcfg](//code.google.com/p/gcfg/) to override settings provided in a
+configuration file.
+
+
+```Go
+import "github.com/Pacien/envcfg"
+```
+
+
+Documentation
+-------------
+
+Package documentation can be found on [GoDoc](//godoc.org/github.com/Pacien/envcfg)
+
+
+Usage example
+-------------
+
+Set environment variables:
+
+```Bash
+export PORT=8080
+export USER_PASSWORD="S3cUrE"
+```
+
+
+Create a struct optionally with tagged fields and/or already set values, then call the `ReadInto` function to read
+the values set in the environment variables.
+
+```Go
+package main
+
+import (
+        "fmt"
+        "github.com/Pacien/envcfg"
+)
+
+type Config struct {
+        Server struct {
+                Port        int `env:"PORT" absenv:"true"`
+        }
+        User struct {
+                Username    string
+                Password    string
+        }
+}
+
+var cnf Config
+
+func (c *Config) setDefaults() *Config {
+        c.User.Username = "root"
+        c.User.Password = "password"
+        return c
+}
+
+func init() {
+        cnf.setDefaults()
+
+        _, errs := envcfg.ReadInto(&cnf)
+        if len(errs) != 0 {
+                fmt.Println(errs)
+        }
+}
+
+func main() {
+        fmt.Println(cnf)
+}
+```
+
+
+Output of the previous program:
+
+```Bash
+{{8080} {root S3cUrE}}
+```
+
+
+See tests for other examples.
+
+
+License
+-------
+
+This program is published under the MIT License.
+See the LICENSE.txt file.