This is the beginnings of a alternative version of the PDP-7 Unix

system which corresponds to a later development point, around mid-1971,
where the system had lost the "dd" directory and gained . and ..
entries. This is close to the system as described in
http://www.tuhs.org/Archive/PDP-11/Distributions/research/McIlroy_v0/UnixEditionZero.txt
except there are no pathnames.

To use this version: cd build; make alt; make altrun

src/other/wktchrm.s

@@ -0,0 +1,41 @@
+" Alternative chrm: chrm file [file file ...]
+"
+" Unlink the named files
+
+   lac 017777			" Go to the argc
+   tad d1			" Skip past the argc
+   dac 2f			" Save pointing at cmd name, we will skip later
+   lac 017777 i			" How many arguments do we have?
+   sad d4
+     sys exit			" None, so exit
+   tad dm4			" Subtract 1
+   dac 017777 i			" and save in the argc
+
+1:
+   lac 017777 i			" Any arguments left?
+   sna
+     sys exit			" No, exit the program
+   tad dm4			" Subtract 4 from the argc and update it
+   dac 017777 i
+   lac 2f			" Move up to the next filename
+   tad d4
+   dac 2f			" and save it in the unlink arg
+   sys unlink; 2:0		" Unlink the file
+   sma
+     jmp 1b			" Loop back if the unlink was OK, or issue err
+   lac 2b			" Copy the filename pointer below
+   dac 2f
+   lac d1			" Write the filename on stdout
+   sys write; 2:0; 4
+   lac d1
+   sys write; 1f; 2		" Write " ?\n" on stdout
+   jmp 1b			" and loop back
+
+1:
+   040077;012000		" String literal " ?\n"
+dd:
+   <dd>;040040;040040;040040	" Filename dd
+d1: 1
+d4: 4
+d5: 5
+dm4: -4

src/other/wktls.s

@@ -23,7 +23,9 @@ argloop:
      jmp setlong
 
    lac argptr		" It wasn't -l, so save it as the dir to open
+#ifndef NO_DD
    dac 8f
+#endif
    dac 9f
    skp
 
@@ -79,7 +81,11 @@ entryloop:
    lac bufptr
    dac statfile		" Copy the pointer to the status call
    lac statbufptr	" Get the file's details into the statbuf
+#ifdef NO_DD
+   sys status; statfile:0
+#else
    sys status; 8:curdir; statfile:0
+#endif
    spa
      jms fileend