sys

README

Sys

Readdir

List and walk directory using system utils ls. This offer an alternative to stdlib's filepath.Walk(). Their behaviours are the same most of the time (read from ls is much slower though), but it's the rare cases that they are different make this alternative useful (on network devices differences are observed, so as during travis-CI build broken)

TODO

• Investige why the difference (filepath.Walk() read system blocks directly);
• Determined test cases to see who is right;
• Benchmark the slow down.

Documentation

Overview

Package sys provides system level utilities.

Index

• func CheckPid(pid int) error
• func GetFileMd5(path string) (string, error)
• func La(name string) ([]string, error)
• func ReadDir(dirname string) ([]os.FileInfo, error)
• func RunCmd(ctx context.Context, name, arg, wd, logFile string, ...) (err error)
• func Walk(root string, walkFn filepath.WalkFunc) error
• type CmdHook
  • func SignalExit(sig syscall.Signal) CmdHook

Functions

func CheckPid

func CheckPid(pid int) error

CheckPid checks if the process of pid exists. Ref: https://stackoverflow.com/questions/15204162/check-if-a-process-exists-in-go-way

func GetFileMd5

func GetFileMd5(path string) (string, error)

GetFileMd5 computes the file MD5 as IO stream; note that this might takes time for large file.

func La

func La(name string) ([]string, error)

La lists all files of the directory including hidden files and self/parent directory; it's behaviour is the same as calling `ls -a`.

func ReadDir

func ReadDir(dirname string) ([]os.FileInfo, error)

ReadDir mimic the behaviour of ioutil.ReadDir (reads the directory named by dirname and returns a list of directory entries sorted by filename), but use `ls -a` and string parsing internally.

func RunCmd

func RunCmd(ctx context.Context, name, arg, wd, logFile string, afterStartFunc, doneFunc CmdHook) (err error)

RunCmd runs a command with specific arg in a blocking way; it calls doneFunc when the context is done.

func Walk

func Walk(root string, walkFn filepath.WalkFunc) error

Walk walks the file tree rooted at root, calling walkFn for each file or directory in the tree, including root. All errors that arise visiting files and directories are filtered by walkFn. The files are walked in lexical order, which makes the output deterministic but means that for very large directories Walk can be inefficient. Walk does not follow symbolic links.

Types

type CmdHook

type CmdHook func(*exec.Cmd, io.WriteCloser)

CmdHook gives access to the executed Cmd and its stdin.

func SignalExit

func SignalExit(sig syscall.Signal) CmdHook

SignalExit sends SIGNAL to exit the process.