Printing a Node's name as described in the previous section works because the string representation of a Node object is the name of the file. If you want to do something other than print the name of the file, you can fetch it by using the builtin Python str function. For example, if you want to use the Python os.path.exists to figure out whether a file exists while the SConstruct file is being read and executed, you can fetch the string as follows:

import os.path
program_list = Program('hello.c')
program_name = str(program_list[0])
if not os.path.exists(program_name):
    print program_name, "does not exist!"
      

Which executes as follows on a POSIX system:

% scons -Q
hello does not exist!
cc -o hello.o -c hello.c
cc -o hello hello.o