GAMBAS BOOK 3.19.1

The Stat (gb) class provides you with all the information returned by the system about a particular file. It must be emphasised that a Stat object is unsuitable for making changes to file properties! The class cannot be created.

• The Stat() function returns a Stat object with which you can read out information on file and directory properties.
• The information is read out for exactly one selected file, whose path you must specify in the Path property → Table 19.3.0.1.1.
• Attention: Six types of files are distinguished → Chapter 19.3.0.2.
• Note that the information about a file is static when using this class because it has been read out at a certain point in time. If you want to record and evaluate certain changes to a selected file dynamically at runtime (via a task), then you will find the Watch class suitable for this in the gb.inotify component.

The Stat class has these properties:

Table 19.3.0.1.1 : Properties of the class Stat

The type of a file can be described by one of the following constants:

Table 19.3.0.2.1 : File type constants of the Stat class

The .Stat.Perm (gb) virtual class describes the file permissions for the selected file and can be used like a read-only array.

Table 19.3.0.3.1 : Properties of the .Stat.Perm class

In all three cases, the string contains the following characters:

• r → for the read permission,
• w → for the write permission,
• x → for the execute right,

if the respective right has been granted. In particular, no character is output for missing permissions. This differs from the output of commands like 'ls -l', where missing permissions are noted with a minus sign at their fixed position.

First, a temporary file is generated in the presented project and a string is inserted as content. Then the file permissions are explicitly changed. Then a Stat object is generated and the file information of the temporary file is read out and displayed in the console of the IDE.

The source code is given in full:

' Gambas class file
 
Public sFilePath As String = Temp(".datei")
 
Public Sub Form_Open()
  Dim sGroup As String
 
  FMain.Center
  FMain.Resizable = False
 
  Exec ["id", "-gn"] To sGroup ' Gruppe des aktuellen Benutzers ermitteln
  sGroup = Trim$(sGroup)
 
  Shell Subst$("touch &1; echo 'TEST TEXT TEXT' > &1", sFilePath) Wait
  Chown sFilePath To User.Name
  Chmod sFilePath To "rwxrw-r--"
  Chgrp sFilePath To sGroup
 
End
 
Public Sub btnGetInformation_Click()
  Dim FileInfo As Stat
  Dim vValue As Variant
  Dim aTypes As String[]
  Dim cCollection As Collection
 
  aTypes = ["Normale Datei", "Verzeichnis", "Gerät", "Pipe (FIFO)", "Socket", "Symbolischer Link"]
 
  FileInfo = Stat(sFilePath)
 
  cCollection = New Collection
' cCollection[Key As String] = Value As Variant → Zuerst der Schlüssel und dann der Wert
  cCollection["Pfad = "] = FileInfo.Path
  cCollection["Datei-Typ = "] = aTypes[FileInfo.Type - 1]
  cCollection["Rechte = "] = FileInfo.Auth
  cCollection["Datei-Modus = "] = FileInfo.Mode
  cCollection["Benutzer = "] = FileInfo.User
  cCollection["Gruppe = "] = FileInfo.Group
  cCollection["Versteckt? = "] = FileInfo.Hidden
  cCollection["Letzter Zugriff auf die Datei   = "] = FileInfo.LastAccess
  cCollection["Letzte Änderung Datei-Inhalt    = "] = FileInfo.LastModified
  cCollection["Letzte Änderung Datei-Attribute = "] = FileInfo.LastChange
  cCollection["Datei-Größe = "] = FileInfo.Size & " Byte"
  cCollection["Sticky-Bit gesetzt? = "] = FileInfo.Sticky
  If FileInfo.Link = Null Then
     cCollection["Symbolischer Link ? = "] = "Nein"
  Else
     cCollection["Symbolischer Link ? = "] = FileInfo.Link
  Endif
  cCollection["Benutzer-Rechte = "] = FileInfo.Perm.User
  cCollection["Gruppen-Rechte  = "] = FileInfo.Perm.Group
  cCollection["Andere-Rechte   = "] = FileInfo.Perm.Other
 
  For Each vValue In cCollection
    Print cCollection.Key, vValue
  Next
 
  Print "Pfad = ", sFilePath; "   Recht R+W  = ", Access(sFilePath, gb.Read Or gb.Write)
  Print "Pfad = ", sFilePath; "   Recht R    = ", Access(sFilePath, gb.Read)
  Print "Pfad = ", sFilePath; "   Recht W    = ", Access(sFilePath, gb.Write)
  Print "Pfad = ", sFilePath; "   Recht X    = ", Access(sFilePath, gb.Exec)
' gb.read ist Standard, wenn das optionale Mode-Argument fehlt
  Print "Pfad = ", sFilePath; "   Recht (R)  = ", Access(sFilePath)
 
End

Output in the console of the IDE:

Pfad =         /tmp/gambas.1000/6251/.datei.tmp
Datei-Typ =    Normale Datei
Rechte =       rwxrw-r--
Datei-Modus =  500
Benutzer = 	hans
Gruppe = 	hans
Versteckt? = 	True
Letzter Zugriff auf die Datei   = 01.10.2015 14:32:10
Letzte Änderung Datei-Inhalt    = 01.10.2015 14:32:10
Letzte Änderung Datei-Attribute = 01.10.2015 14:32:10
Datei-Größe = 	15 Byte
Sticky-Bit gesetzt? = False
Symbolischer Link ? = Nein
Benutzer-Rechte = 	rwx
Gruppen-Rechte  = 	rw
Andere-Rechte   = 	r
Pfad = 	/tmp/gambas.1000/6251/.datei.tmp  Recht R+W  = 	True
Pfad = 	/tmp/gambas.1000/6251/.datei.tmp  Recht R    = 	True
Pfad = 	/tmp/gambas.1000/6251/.datei.tmp  Recht W    = 	True
Pfad = 	/tmp/gambas.1000/6251/.datei.tmp  Recht X    = 	True
Pfad = 	/tmp/gambas.1000/6251/.datei.tmp  Recht (R)  = 	True

An alternative to the use of the virtual class .Stat.Perm is the Access function, about which you can read information at → http://gambaswiki.org/wiki/lang/access and which was also used selectively in the above project.

The three instructions CHGRP, CHMOD and CHOWN are available for changing file attributes → chapter 19.3.1.