add test-wcat.sh wrapper, and README

initial-utilities/wcat/README.md

@@ -3,10 +3,10 @@ In this directory, you should write the program `wcat.c` and compile it into
 the binary `wcat`.
 
 After doing so, you can run the tests from this directory by running the
-`run-tests.sh` script. If all goes well, you will see:
+`test-wcat.sh` script. If all goes well, you will see:
 
 ```sh
-prompt> ../../tester/run-tests.sh
+prompt> ./test-wcat.sh
 test 1: passed
 test 2: passed
 test 3: passed
@@ -17,3 +17,8 @@ test 7: passed
 prompt>
 ```
 
+`test-wcat.sh` is just a wrapper for the `run-tests.sh` script in the `tester`
+directory of this repository. This program has a few options; see the relevant
+README for details.
+
+

initial-utilities/wcat/test-wcat.sh

@@ -0,0 +1,10 @@
+#! /bin/bash
+
+if ! [[ -x wcat ]]; then
+    echo "wcat executable does not exist"
+    exit 1
+fi
+
+../../tester/run-tests.sh $*
+
+