screen 3.09.11 port to POSIX 1003.1-2001 hosts

[Paul Eggert]

The new POSIX standard is now official (IEEE Std 1003.1-2001), and it
has removed support for some obsolete utility options that 'screen'
uses.  Basically, the new POSIX has removed digit-string options
(e.g., "tail -1") and options beginning with "+" (e.g., "sort +1").
I'm using an experimental environment that insists on the new
standard, so I tend to run into these problems before other people do.

Here is a proposed patch for screen 3.09.11.

2002-02-22  Paul Eggert  <address@hidden>

        Port to POSIX 1003.1-2001 hosts.            
        * ./etc/toolcheck (reply): Rewrite to avoid head -1.
        * ./etc/completer.zsh (screendir): Rewrite to avoid tail -1.
        * ./Makefile.in (mdepend): Try sort -k first, falling back on sort +1.

===================================================================
RCS file: ./etc/toolcheck,v
retrieving revision 3.9.11.0
retrieving revision 3.9.11.1
diff -pu -r3.9.11.0 -r3.9.11.1
--- ./etc/toolcheck     2001/07/18 15:48:19     3.9.11.0
+++ ./etc/toolcheck     2002/02/23 06:29:55     3.9.11.1
@@ -5,7 +5,7 @@
 # 24.7.95 jw.
 
 retval=0
-reply="`sh -version 2>&1 < /dev/null | head -1`"
+reply="`sh -version 2>&1 < /dev/null | sed q`"
 case "$reply" in
        GNU*1.14.3*)    
                echo "- sh  is '$reply'";
@@ -21,7 +21,7 @@ case "$reply" in
        *)      ;;
 esac
 
-reply="`sed --version 2>&1 < /dev/null | head -1`"
+reply="`sed --version 2>&1 < /dev/null | sed q`"
 case "$reply" in
        GNU\ sed\ version\ 2.0[34])
                echo "- sed is '$reply'";
===================================================================
RCS file: ./etc/completer.zsh,v
retrieving revision 3.9.11.0
retrieving revision 3.9.11.1
diff -pu -r3.9.11.0 -r3.9.11.1
--- ./etc/completer.zsh 2001/12/09 18:18:37     3.9.11.0
+++ ./etc/completer.zsh 2002/02/23 06:29:55     3.9.11.1
@@ -45,9 +45,9 @@ case $state in
   # Complete folder names.
   local screendir
 
-    screendir=(`screen -ls | grep Socket | tail -1 | sed -e 's/\.$//' | awk 
'{print $NF;}'`)
+    screendir=(`screen -ls | grep Socket | sed -n -e 's/\.$//' -e '$p' | awk 
'{print $NF;}'`)
 
   _wanted files expl 'screen process' _path_files -W screendir
 ;;
 esac
-    
\ No newline at end of file
+    
===================================================================
RCS file: ./Makefile.in,v
retrieving revision 3.9.11.0
retrieving revision 3.9.11.1
diff -pu -r3.9.11.0 -r3.9.11.1
--- ./Makefile.in       2002/02/14 13:36:33     3.9.11.0
+++ ./Makefile.in       2002/02/23 06:29:55     3.9.11.1
@@ -248,7 +248,7 @@ mdepend: $(CFILES) term.h
          echo `echo "$$i" | sed -e 's/.c$$/.o/'`": $$i" `\
             cc -E $$i |\
             grep '^# .*"\./.*\.h"' |\
-            sort -t'"' -u +1 -2 |\
+            (sort -t'"' -u -k 2,2 2>/dev/null || sort -t'"' -u +1 -2) |\
             sed -e 's/.*"\.\/\(.*\)".*/\1/'\
           ` >> DEPEND ; \
        done