# System Package system contains some functions about os, runtime, shell command.
## Source: [https://github.com/duke-git/lancet/blob/main/system/os.go](https://github.com/duke-git/lancet/blob/main/system/os.go)
## Usage: ```go import ( "github.com/duke-git/lancet/system" ) ```
## Index - [IsWindows](#IsWindows) - [IsLinux](#IsLinux) - [IsMac](#IsMac) - [GetOsEnv](#GetOsEnv) - [SetOsEnv](#SetOsEnv) - [RemoveOsEnv](#RemoveOsEnv) - [CompareOsEnv](#CompareOsEnv) - [ExecCommand](#ExecCommand)
## Documentation ### IsWindows

Check if current os is windows.

Signature: ```go func IsWindows() bool ``` Example: ```go import ( "fmt" "github.com/duke-git/lancet/system" ) func main() { isOsWindows := system.IsWindows() fmt.Println(isOsWindows) } ``` ### IsLinux

Check if current os is linux.

Signature: ```go func IsLinux() bool ``` Example: ```go import ( "fmt" "github.com/duke-git/lancet/system" ) func main() { isOsLinux := system.IsLinux() fmt.Println(isOsLinux) } ``` ### IsMac

Check if current os is macos.

Signature: ```go func IsMac() bool ``` Example: ```go import ( "fmt" "github.com/duke-git/lancet/system" ) func main() { isOsMac := system.IsMac fmt.Println(isOsMac) } ``` ### GetOsEnv

Gets the value of the environment variable named by the key.

Signature: ```go func GetOsEnv(key string) string ``` Example: ```go import ( "fmt" "github.com/duke-git/lancet/system" ) func main() { fooEnv := system.GetOsEnv("foo") fmt.Println(fooEnv) } ``` ### SetOsEnv

Sets the value of the environment variable named by the key.

Signature: ```go func SetOsEnv(key, value string) error ``` Example: ```go import ( "fmt" "github.com/duke-git/lancet/system" ) func main() { err := system.SetOsEnv("foo", "foo_value") fmt.Println(err) } ``` ### RemoveOsEnv

Remove a single environment variable.

Signature: ```go func RemoveOsEnv(key string) error ``` Example: ```go import ( "fmt" "github.com/duke-git/lancet/system" ) func main() { err := system.RemoveOsEnv("foo") if err != nil { fmt.Println(err) } } ``` ### CompareOsEnv

Get env named by the key and compare it with comparedEnv.

Signature: ```go func CompareOsEnv(key, comparedEnv string) bool ``` Example: ```go import ( "fmt" "github.com/duke-git/lancet/system" ) func main() { system.SetOsEnv("foo", "foo_value") res := system.CompareOsEnv("foo", "foo_value") fmt.Println(res) //true } ``` ### CompareOsEnv

use shell /bin/bash -c(linux) or cmd (windows) to execute command.

Signature: ```go func ExecCommand(command string) (stdout, stderr string, err error) ``` Example: ```go import ( "fmt" "github.com/duke-git/lancet/system" ) func main() { out, errout, err := system.ExecCommand("ls") fmt.Println(out) fmt.Println(errout) fmt.Println(err) } ```