implement cwd on linux.

README.rst

@@ -79,6 +79,7 @@ Current Status
     - cmdline (linux)
     - create_time (linux)
     - status (linux)
+    - cwd (linux)
     - exe (freebsd)
     - uids (linux)
     - gids (linux)
@@ -99,7 +100,6 @@ Current Status
   - Process class
 
     - parent
-    - cwd
     - username
     - ionice
     - rlimit

process_linux.go

@@ -37,7 +37,7 @@ func NewProcess(pid int32) (*Process, error) {
 	// Fill Process information from fillFuncs
 	var wg sync.WaitGroup
 	funcs := []fillFunc{fillFromStat, fillFromStatus, fillFromfd,
-		fillFromCmdline, fillFromStatm}
+		fillFromCmdline, fillFromStatm, fillFromCwd}
 
 	wg.Add(len(funcs))
 	for _, f := range funcs {
@@ -77,6 +77,18 @@ func fillFromfd(pid int32, p *Process) error {
 	return nil
 }
 
+// Get cwd from /proc/(pid)/cwd
+func fillFromCwd(pid int32, p *Process) error {
+	cwdPath := filepath.Join("/", "proc", strconv.Itoa(int(pid)), "cwd")
+	cwd, err := os.Readlink(cwdPath)
+	if err != nil {
+		return err
+	}
+	p.Cwd = string(cwd)
+
+	return nil
+}
+
 // Get cmdline from /proc/(pid)/cmdline
 func fillFromCmdline(pid int32, p *Process) error {
 	cmdPath := filepath.Join("/", "proc", strconv.Itoa(int(pid)), "cmdline")