File tcsh-6.20.00-postcmd.patch of Package tcsh.19070

https://bugs.astron.com/view.php?id=74#c3238
This is the upstream fix backported from tcsh-6.21.00

Avoid trouble with e.g.

 alias postcmd false
 set counter=1
 while ($counter > )
     @ counter--
     echo $counter
 end

and similar scriptlets, maybe there is a better solution to
protect dowhile(), nevertheless this works.

--- 
 tcsh-6.20.00/sh.lex.c  |    4 +++-
 tcsh-6.20.00/tc.func.c |    2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

--- tcsh-6.20.00/sh.lex.c
+++ tcsh-6.20.00/sh.lex.c	2019-05-09 05:35:56.696918508 +0000
@@ -142,6 +142,7 @@ static time_t a2time_t (Char *);
  * special parsing rules apply for source -h
  */
 extern int enterhist;
+extern int postcmd_active;
 
 int
 lex(struct wordent *hp)
@@ -153,7 +154,8 @@ lex(struct wordent *hp)
     histvalid = 0;
     histline.len = 0;
 
-    btell(&lineloc);
+    if (!postcmd_active)
+	btell(&lineloc);
     hp->next = hp->prev = hp;
     hp->word = STRNULL;
     hadhist = 0;
--- tcsh-6.20.00/tc.func.c
+++ tcsh-6.20.00/tc.func.c	2019-05-09 05:38:14.310299504 +0000
@@ -57,7 +57,7 @@ extern time_t t_period;
 extern int just_signaled;
 static int precmd_active = 0;
 static int jobcmd_active = 0; /* GrP */
-static int postcmd_active = 0;
+int postcmd_active = 0;
 static int periodic_active = 0;
 static int cwdcmd_active = 0;	/* PWP: for cwd_cmd */
 static int beepcmd_active = 0;