dependency test compatbility notice

dependency-test.sh

@@ -1,5 +1,10 @@
 #!/bin/sh
 
+# Compatible with  bash  dash  zsh
+# but not with     fish
+
+
+
 br=0 # build required
 bs=0 # build recommended
 bo=0 # build optional

manuals/ponysay.texinfo

@@ -871,6 +871,9 @@ transparent background, and pixelated are the properties that makes a picture go
 
 We have provided a script that should run one most, if not all shells, named
 @file{./dependency-test.sh} that will help you track down any missing package.
+The script works in @command{bash}, @command{dash} and @command{zsh}, but not
+in @command{fish}, so case you @command{sh} links to @command{fish}, run
+@command{bash dependency-test.sh} (or with one of the other compatible shells.)
 
 @menu
 * Required runtime dependencies::       Required runtime dependencies.