pam_mkhomedir.so  [
        silent
      ] [
        umask=mode
      ] [
        skel=skeldir
      ]
      The pam_mkhomedir PAM module will create a users home directory
      if it does not exist when the session begins. This allows users
      to be present in central database (such as NIS, kerberos or LDAP)
      without using a distributed file system or pre-creating a large
      number of directories. The skeleton directory (usually
      /etc/skel/) is used to copy default files
      and also sets a umask for the creation.
    
The new users home directory will not be removed after logout of the user.
- 
          
silent Don't print informative messages.
- 
          
umask=mask The user file-creation mask is set to
mask. The default value of mask is 0022.- 
          
skel=/path/to/skel/directory Indicate an alternative
skeldirectory to override the default/etc/skel.
- PAM_BUF_ERR
 Memory buffer error.
- PAM_CRED_INSUFFICIENT
 Insufficient credentials to access authentication data.
- PAM_PERM_DENIED
 Not enough permissions to create the new directory or read the skel directory.
- PAM_USER_UNKNOWN
 User not known to the underlying authentication module.
- PAM_SUCCESS
 Environment variables were set.
A sample /etc/pam.d/login file:
  auth       requisite   pam_securetty.so
  auth       sufficient  pam_ldap.so
  auth       required    pam_unix.so
  auth       required    pam_nologin.so
  account    sufficient  pam_ldap.so
  account    required    pam_unix.so
  password   required    pam_unix.so
  session    required    pam_mkhomedir.so skel=/etc/skel/ umask=0022
  session    required    pam_unix.so
  session    optional    pam_lastlog.so
  session    optional    pam_mail.so standard