Getenv Read (numeric) shell environment variables into a synth

Getenv(key, defaultval)

Tries to grab a shell environment variable (with name key) and convert it to a floating-point value, which is output.

If the environment variable is not set, defaultval is output.

If the environment variable cannot be converted to a floating-point value, the output is zero.

NOTE: the shell context is that of the server, not the client.

Server.local.quit; // If server running, need to stop it for this example

// We'll modify the server boot procedure to set our env var...

~realserverprogram = Server.program;

Server.program = "export PANCREAS=220;" + Server.program

s.boot;

(

x = {

// Env var specifies frequency.

// If you change the env var name to one that isn't set, 440 is used.

SinOsc.ar(Getenv(\PANCREAS, 440), 0, 0.1);

}.play(Server.local);

)

x.free;

// This should restore the variable to what it was

Server.program = ~realserverprogram;