Print err in stderr, Find out docker rootfs.collector

When I use godo, error infomation comes along with other output, so
change all err report into stderr. And I listen to `pivot_root` sys-
call to find out the root file system of dockers. However, I'm afraid
of causing too more delay, so don't check rootfs of ppid and record
in the pid. Besides, the method to deal with pivot_root is hardcoded,
which may causes crush.

Shall I listen to the chdir syscall to find out exact cwd? Maybe It's
useful to the pivot_root?

Next step: Find out appropriate data stracture, and add more file
operations to be watched. This task must be completed this week.

1 files changed, 4 insertions, 2 deletions

diff --git a/src/global.go b/src/global.go
index b6635c9..349ba6c 100644
--- a/src/global.go
+++ b/src/global.go
@@ -14,11 +14,12 @@ const (
         FILEOPEN
         FILECLOSE
         FILEWRITE
+        PIVOTROOT
         TYPENUM
 )
 
 func (et eventType) String() string {
-        names := []string{"NEWPID", "PIDEXIT", "EXECVE", "FILEOPEN", "FILECLOSE", "FILEWRITE", "TYPENUM"}
+        names := []string{"NEWPID", "PIDEXIT", "EXECVE", "FILEOPEN", "FILECLOSE", "FILEWRITE", "PIVOTROOT", "TYPENUM"}
         if et < NEWPID || et > TYPENUM {
                 return "Unknown"
         }
@@ -32,12 +33,13 @@ type Event struct {
         ppid, parentTgid int
         syscall          int
         syscallParam     [4]uint64
-        pathName         string
         argc             int
         argv             []string
         cwd              string
         exit_code        uint64
         exit_signal      int
+        srcPath          string
+        destPath         string
 }
 
 var wg sync.WaitGroup        // 掌管协程