import os,tempfile,dircache,string,commands



def read_file(filename):
	"""
	read from the file whose name is given
	@param filename String : name of file to read from
	@return String: content of given file or None
	"""
	try:
		f = open(filename,"r")
		filecontent = f.read()
		f.close()
	except:
		#TODO:if debug >=1:
		print "(EE)[%s]: \"%s\" is not readable!"%(__name__, filename)
		return ""
	return filecontent




def is_dir_readable(path):
	""" 
	Gets the name of a directory.
	returns True if dir is readable, else False.
	"""
	return os.access(path,os.R_OK)
	


def write_file(filename,content):
	"""
	Write content to the given filename.
	gets: filename,content.
	"""
	try:
		f = open(filename,"w")#oeffnen und schliessen =>
		f.close()			#datei ist jetzt genullt
		f = open(filename,"a")	#anhaengend oeffnen
		f.write(content)
		f.close()
		return ""
	except:
		#TODO: debug
		#if self.debug >=1:
		print "(EE)[%s]: \"%s\" is not writeable!"%(__name__, filename)
		return filename

def basename(filename):
	return os.path.basename(filename)
	

def make_all_dirs_absolute(prefix,dirlist):
	"""
	this function gets an absolute pathname and a list of pathnames 
	relative to the first. It returns this list, but with absolute
	entries.
	"""
	ret=[]
	for element in dirlist:
		ret.append(os.path.normpath(prefix+"/"+element))
	return ret
	

def gen_temp_dir(prefix='pk'):
	'''returns the name of a secure temporary directory 
	with optional prefix as parameter'''
	dirname=tempfile.mkdtemp("",prefix)
	dirname+="/"
	return dirname

def gen_temp_file(suffix="--gnugo"):
	"""
	returns the name of a generated temporay file.
	optionally gets a suffix for the filename.
	"""
	return tempfile.mkstemp(suffix)[1]