diff --git a/tests/data/illegal-mode.data b/tests/data/illegal-mode.data
new file mode 100644
index 0000000..d4ba344
--- /dev/null
+++ b/tests/data/illegal-mode.data
@@ -0,0 +1,7 @@
+# A non-compressing DAT (DDS-1)
+# The manufacturer, model, and revision strings can be obtained,
+# from the file /proc/scsi/scsi (cat /proc/scsi/scsi).
+manufacturer=XYZ model = "UVW1" {
+scsi2logical=1 can-bsr can-partitions auto-lock
+mode1 blocksize=0
+modeABC blocksize=1024 }
diff --git a/tests/mt-cli.test b/tests/mt-cli.test
new file mode 100644
index 0000000..fc1dc6f
--- /dev/null
+++ b/tests/mt-cli.test
@@ -0,0 +1,34 @@
+# Wrong argument
+./mt -x
+>>>2 /usage: /
+>>>= 1
+
+# Missing tape argument
+./mt -f
+>>>2 /usage: /
+>>>= 1
+
+# Unknown command
+./mt to-the-moon
+>>>2 /mt: unknown command "to-the-moon"/
+>>>= 1
+
+# Too many arguments
+./mt rewind 1
+>>>2 /mt: too many arguments for the command 'rewind'\./
+>>>= 1
+
+# Ambigous command
+./mt l
+>>>2 /mt: ambiguous command "l"/
+>>>= 1
+
+# Shortened but not ambiguous command.
+./mt rewi 1
+>>>2 /mt: too many arguments for the command 'rewind'\./
+>>>= 1
+
+# Densities command - the only one not requiring a tape.
+./mt densities
+>>> /LTO-6/
+>>>= 0
diff --git a/tests/mt-errors.test b/tests/mt-errors.test
new file mode 100644
index 0000000..bef9437
--- /dev/null
+++ b/tests/mt-errors.test
@@ -0,0 +1,4 @@
+# Wrong tape argument
+./mt -f /dev/no-such-tape rewind
+>>>2 /no-such-tape: No such file or directory/
+>>>= 1
diff --git a/tests/stinit-errors.test b/tests/stinit-errors.test
new file mode 100644
index 0000000..4fed36f
--- /dev/null
+++ b/tests/stinit-errors.test
@@ -0,0 +1,51 @@
+# Check handling of missing file
+./stinit -p -f no-such-database
+>>>2 /Can't find SCSI tape database/
+>>>= 1
+
+# No file passed
+./stinit -p -f
+>>>2 /Usage:/
+>>>= 1
+
+# Wrong arguments
+./stinit -x
+>>>2 /Usage:/
+>>>= 1
+
+# Illegal ordering of arguments
+./stinit -f stinit.def.examples 1000 -
+>>>2 /Usage:/
+>>>= 1
+
+# Check bad mode
+./stinit -v -v -p -f tests/data/illegal-mode.data
+>>> /Errors found!/
+>>>2 /Illegal mode for/
+>>>= 1
+
+# No modes defined
+#./stinit -v -v -f tests/data/no-modes.data
+#>>> /Errors found!/
+#>>>2 /Illegal mode for/
+#>>>= 1
+
+# Wrong tape device
+./stinit -f stinit.def.examples /dev/no-such-tape
+>>>2 /Can't find tape number for name/
+>>>= 0
+
+# Wrong tape number. Well, this is flaky, but let's hope nobody has
+# 1000 tapes.
+./stinit -f stinit.def.examples 1000
+>>>2 /Can't find any device files for tape 1000/
+>>>= 0
+
+./stinit -f stinit.def.examples 1000
+>>>2 /Definition for '1000' failed/
+>>>= 0
+
+# Wrong tape number (non-numeric).
+./stinit -f stinit.def.examples 1000a
+>>>2 /Invalid tape device index '1000a': don't know how to parse 'a'/
+>>>= 0
diff --git a/tests/stinit-parsing.test b/tests/stinit-parsing.test
index 9827880..6636fc6 100644
--- a/tests/stinit-parsing.test
+++ b/tests/stinit-parsing.test
@@ -2,6 +2,11 @@
 ./stinit -p -f stinit.def.examples
 >>>= 0
 
+# Extra arguments ignored while file parsing
+./stinit -p -f stinit.def.examples abc
+>>>2 /Extra arguments .* ignored/
+>>>= 0
+
 # Checking complete stinit parsing
 ./stinit -v -v -p -f stinit.def.examples
 >>> /No errors found./