1 01/12/2018  Pathnames (general information)
 2 
 3 Pathnames are the names of entries in the Multics file system.  These
 4 names may be fully qualified absolute pathnames, or partially qualified
 5 relative pathnames.  In addition, the final entryname of the pathname
 6 may be a starname or an equalname, or the pathname may be followed by
 7 an archive component name, an offset or a symbolic definition.
 8 
 9 
10 Absolute pathnames: An absolute pathname the entryname of a directory,
11 file or link preceded by a series of directory names beginning at the
12 root and leading to the final entryname.  Each directory name and the
13 final entryname are preceded by a greater-than character (">").
14 
15 
16 An absolute pathname always begins with a greater than.  This
17 designates the root directory.  The pathname of the root directory is
18 the only absolute pathname with no entryname.
19 
20 
21 Examples of absolute pathnames:
22    >                  (the root)
23    >tools
24    >udd>Demo>JQUser>myfile
25 
26 
27 Relative pathnames: Relative pathnames are pathnames which are
28 interpreted relative to the working directory.  An entryname or a
29 pathname which does not begin with a greater than character (">") is a
30 relative pathname.  A relative pathname may begin with one or more
31 less-than characters ("<").  Each less-than is interpreted as one
32 directory level closer to the root directory than the working
33 directory.  Any relative pathname may be converted to an absolute
34 pathname if the working directory is known, provided that the relative
35 pathname contains no more less-than characters than there are
36 entrynames in the working directory pathname.
37 
38 
39 Examples of relative pathnames:
40 Assume that the working directory is >udd>Demo>JQUser.
41 
42 Relative pathname                 Absolute pathname
43 ""                 (null path)    >udd>Demo>JQUser
44 <                                 >udd>Demo
45 myfile                            >udd>Demo>JQUser>myfile
46 subdir>myfile                     >udd>Demo>JQUser>subdir>myfile
47 <<NewProj>JQUser                  >udd>NewProj>JQUser
48 <<<tools                          >tools
49 <<<<               (error)
50 
51 
52 Extended pathnames: pathnames can indicate distinctions other than a
53 single segment.  If the segment is an archive, then an archive
54 component pathname can indicate a component in the archive rather than
55 just the entire archive.  If the final entryname is a starname or an
56 entryname, then sets of segments or directories may be designated.
57 When representing Multics pointers, a virtual pointer can designate a
58 single bit of the segment.  If the segment is an object segment, then a
59 virtual pointer or virtual entry can indicate a symbolic definition in
60 the segment or in its associated linkage section.  Note that extended
61 pathnames are not implemented in all contexts, so consult the
62 documentation of a command to discover whether it supports one or more
63 of these conventions.
64 
65 
66 Notes: The following related info segments provide further information
67 about pathnames:
68   entryname.gi.info
69   archive_pathname.gi.info
70   starname.gi.info
71   equalname.gi.info
72   virtual_pointers.gi.info
73   virtual_entry.gi.info