def _test_rename(self):
d = tempfile.mkdtemp()
try:
f = op.join(d, "f.txt")
fid = open(f, "wt")
try:
fid.write("")
finally:
fid.close()
g = op.join(d, "g.txt")
rename(f, g)
self.assertTrue(op.exists(g))
finally:
shutil.rmtree(d)
def _test_rename(self):
d = tempfile.mkdtemp()
try:
f = op.join(d, "f.txt")
fid = open(f, "wt")
try:
fid.write("")
finally:
fid.close()
g = op.join(d, "g.txt")
rename(f, g)
self.assertTrue(op.exists(g))
finally:
shutil.rmtree(d)
def safe_write(target, writer, mode="wb"):
"""a 'safe' way to write to files.
Instead of writing directly into a file, this function writes to a
temporary file, and then rename the file to the target. On sane
platforms, rename is atomic, so this avoids leaving stale
files in inconsistent states.
Parameters
----------
target: str
destination to write to
writer: callable
function which takes one argument, a file descriptor, and
writes content to it
mode: str
opening mode
"""
f = open(target + ".tmp", mode)
try:
writer(f)
finally:
f.close()
rename(target + ".tmp", target)
def safe_write(target, writer, mode="wb"):
"""a 'safe' way to write to files.
Instead of writing directly into a file, this function writes to a
temporary file, and then rename the file to the target. On sane
platforms, rename is atomic, so this avoids leaving stale
files in inconsistent states.
Parameters
----------
target: str
destination to write to
writer: callable
function which takes one argument, a file descriptor, and
writes content to it
mode: str
opening mode
"""
f = open(target + ".tmp", mode)
try:
writer(f)
finally:
f.close()
rename(target + ".tmp", target)
