Starts a particular tool. For an interactive tool,
${tool}_start starts and initializes the tool, leaving the tool
up and running for the test cases; an example is gdb_start, the
start function for GDB. For a batch-oriented tool,
${tool}_start is optional; the recommended convention is to let
${tool}_start run the tool, leaving the output in a variable
called comp_output. Test scripts can then analyze
$comp_output to determine the test results. An example of this
second kind of start function is gcc_start, the start function
for GCC.
DejaGnu itself does not call ${tool}_start. The initialization
module ${tool}_init.exp must call ${tool}_start for
interactive tools; for batch-oriented tools, each individual test script
calls ${tool}_start (or makes other arrangements to run the
tool).
${tool}_start