caffe数据集制作lmdb错误

I0911 11:22:49.966572 16695 convert_imageset.cpp:86] Shuffling data
I0911 11:22:50.252228 16695 convert_imageset.cpp:89] A total of 2354 images.
F0911 11:22:50.252285 16695 db_lmdb.cpp:13] Check failed: mkdir(source.c_str(), 0744) == 0 (-1 vs. 0) mkdir mydata/ResNet-18/build_lmdb//ilsvrc12_train_lmdb failed
*** Check failure stack trace: ***
@ 0x7f24f23215cd google::LogMessage::Fail()
@ 0x7f24f2323433 google::LogMessage::SendToLog()
@ 0x7f24f232115b google::LogMessage::Flush()
@ 0x7f24f2323e1e google::LogMessageFatal::~LogMessageFatal()
@ 0x7f24f2837368 caffe::db::LMDB::Open()
@ 0x403aaf main
@ 0x7f24f1291830 __libc_start_main
@ 0x404b79 _start
@ (nil) (unknown)
Aborted (core dumped)

这么简单错误自己捣鼓半天，把之前生成的lmdb文件夹删了就好了