check for gawk and cleanup comments

ftplugin/logrotate.vim

@@ -7,26 +7,36 @@ if exists("b:did_ftplugin")
 endif
 b:did_ftplugin = 1
 
-def LogrotateHelp(word: string)
-    const searchcmd =<< trim END
-        COLUMNS=80 man logrotate 2>/dev/null | 
-        gawk '/^CONFIGURATION FILE DIRECTIVES/,/^SCRIPTS/' | gawk '
-        /^ {7}%s/,/^[a-z]/ {
-            if(firstLineDone) {
-                if(/^ {0,7}[^ ]/ && !/endscript/)
-                    exit
-            }
-            firstLineDone = 1
-            print(substr($0, 8))
-        }'
-    END
-    printf(join(searchcmd, "\n"), word)
-        ->systemlist()
-        ->popup_atcursor({ "padding": [0, 1, 1, 1] })
-enddef
+b:undo_ftplugin = "setlocal comments< commentstring< formatoptions< omnifunc<"
 
-command -nargs=1 LogRt :call LogrotateHelp(<f-args>)
+var awkcmd: string 
 
-b:undo_ftplugin = "setlocal comments< commentstring< formatoptions< keywordprg<"
+if exists("g:logrotate_awk")
+    awkcmd = g:logrotate_awk
+else
+    awkcmd = "gawk"
+endif
+# Have to use gawk, default awk (mawk) does not support {0,7} syntax
+if executable(awkcmd)
+    def LogrotateHelp(word: string)
+        const searchcmd =<< trim eval END
+            COLUMNS=80 man logrotate 2>/dev/null | 
+            {awkcmd} '/^CONFIGURATION FILE DIRECTIVES/,/^SCRIPTS/' | {awkcmd} '
+            /^ {{7}}%s/,false {{
+                if(firstLineDone && /^ {{0,7}}[^ ]/ && !/endscript/) exit
+                firstLineDone = 1
+                print(substr($0, 8))
+            }}'
+        END
+        printf(join(searchcmd, "\n"), word)
+            ->systemlist()
+            ->popup_atcursor({ "padding": [0, 1, 1, 1] })
+    enddef
 
-setlocal comments=:# commentstring=#\ %s formatoptions-=t formatoptions+=croql keywordprg=:LogRt
+    command -nargs=1 LogRotateHelpCmd :call LogrotateHelp(<f-args>)
+    setlocal keywordprg=:LogRotateHelpCmd
+    b:undo_ftplugin = b:undo_ftplugin .. " keywordprg<"
+endif
+
+setlocal omnifunc=syntaxcomplete#Complete
+setlocal comments=:# commentstring=#\ %s formatoptions-=t formatoptions+=croql