webbrowser.py 文件源码

def _iscommand(cmd):
    """Return True if cmd is executable or can be found on the executable
    search path."""
    if _isexecutable(cmd):
        return True
    path = os.environ.get("PATH")
    if not path:
        return False
    for d in path.split(os.pathsep):
        exe = os.path.join(d, cmd)
        if _isexecutable(exe):
            return True
    return False


# General parent classes