if the test name on the command line is "-", read Lua script from the standard input.

README.md

@@ -61,8 +61,9 @@ The general command line syntax for sysbench is:
   `memory`, `cpu`, etc.), or a name of one of the bundled Lua scripts
   (e.g. `oltp_read_only`), or a *path* to a custom Lua script. If no
   test name is specified on the command line (and thus, there is no
-  *command* too, as in that case it would be parsed as a *testname*),
-  then sysbench expects a Lua script to execute on its standard input.
+  *command* too, as in that case it would be parsed as a *testname*), or
+  the test name is a dash ("`-`"), then sysbench expects a Lua script to
+  execute on its standard input.
 
 - *command* is an optional argument that will be passed by sysbench to
   the built-in test or script specified with *testname*. *command*

src/sysbench.c

@@ -1430,7 +1430,7 @@ int main(int argc, char *argv[])
 
   print_header();
 
-  if (sb_globals.testname != NULL)
+  if (sb_globals.testname != NULL && strcmp(sb_globals.testname, "-"))
   {
     /* Is it a built-in test name? */
     test = find_test(sb_globals.testname);
@@ -1468,6 +1468,8 @@ int main(int argc, char *argv[])
   }
   else
   {
+    sb_globals.testname = NULL;
+
     if (SB_ISATTY())
       log_text(LOG_NOTICE, "Reading the script from the standard input:\n");
 

tests/t/cmdline.t

@@ -85,7 +85,7 @@
   
   Threads fairness:
       events (avg/stddev):           1.0000/0.00
-      execution time (avg/stddev):   0.0000/0.00
+      execution time (avg/stddev):   *.*/0.00 (glob)
   
 ########################################################################
 Command line options tests
@@ -317,3 +317,20 @@ Command line options tests
   argv[3] = cmdline.lua
   argv[4] = prepare
   sysbench.cmdline.command = prepare
+
+  $ sysbench - <<EOF
+  > print("hello")
+  > EOF
+  sysbench * (glob)
+  
+  hello
+
+  $ sysbench - prepare <<EOF
+  > function prepare()
+  >   print("prepare")
+  > end
+  > print("global")
+  > EOF
+  sysbench * (glob)
+  
+  global