New ls -l reporting

  

Figure 1: Sample directory listing

 One user feature added to support the data migration system is a set of additional flags which indicate archive state and which are displayed via the ls -l command. Files typically have a ``-'' in the left-most column. With this change, an archived file has an ``a'', and an archived, non-resident file is indicated with an ``A''. This change was implemented by increasing the functionality of the strmode(3) subroutine, and by adding two extra flags to the mode value returned by a stat(2) call. For instance in the directory listing shown in Figure 1, it is clear that the file dmfs.h has been archived, and the file Inside_AT.pdf has both been archived and also been made non-resident.

These flags are available for use by all file systems which possess the concept of file archival attributes. For instance, the NetBSD FAT (MS-DOS) file system implementation has been extended to indicate archival state using this mechanism.