Fortify command, file and pipe delimiters

Often it helps to see better where output begins or end exactly.

src/include-bash/pretty.sh

@@ -378,11 +378,10 @@ _pretty__echo_cmd() {
     #
     # Print command line, launch it and report exit status
     #
-    local c=\$
-    test "$(id -u)" -eq 0 && c="#"
-    echo "$c $*"
-    "$@"
-    echo "^ exit status: $?"
+    local es
+    echo "-- begin command $* --"
+    "$@"; es=$?
+    echo "-- end command ($es) $* --"
 }
 
 
@@ -393,10 +392,13 @@ _pretty__echo_files() {
     local fp
     for fp in "$@"; do
         if test "$fp" = "-"; then
+            echo "-- begin pipe --"
             cat
+            echo "-- end pipe --"
         elif test -s "$fp" || test "$fp" = "/dev/stdin"; then
-            echo "-- $fp --"
+            echo "-- begin file $fp --"
             cat "$fp"
+            echo "-- end file $fp --"
         fi
     done
 }