Python is unable to open my simlinked file. I made sure the file exists and I can access it. I was under the impression that symlinks are resolved on the OS level so Python would never know about it.
therold@therold:~/Programming/ML/deeptank/dataset/inc (master)$ ls -lisa /Users/therold/Programming/ML/deeptank/dataset/inc/training/tanks/matilda-iv_689.png
7870541 8 lrwxr-xr-x 1 therold staff 46 13 Mai 16:44 /Users/therold/Programming/ML/deeptank/dataset/inc/training/tanks/matilda-iv_689.png -> ../training_data/matilda-iv/matilda-iv_689.png
OSX is clearly able resolve the symlinked image file. However the Python open() method fails me:
therold@therold:~/Programming/ML/deeptank/dataset/inc (master)$ python
Python 2.7.10 (default, Sep 23 2015, 04:34:21)
[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.72)] on darwin
>>> open("/Users/therold/Programming/ML/deeptank/dataset/inc/training/tanks/matilda-iv_689.png")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
IOError: [Errno 2] No such file or directory: '/Users/therold/Programming/ML/deeptank/dataset/inc/training/tanks/matilda-iv_689.png'
>>>
Any ideas what I am doing wrong? Help is much appreciated.
Any ideas what I am doing wrong?
The target of the symbolic link doesn't exist.
I don't understand why I was able to resolve it in the ls statement in my question.
You weren't.
The ls command by default operates on the link itself, not on the target of the link. Absent the -L option, ls never attempts to resolve the symbolic link.
Consider a directory with these two files:
$ ls -l
-rw-rw-r-- 1 me me 6 May 13 11:58 a
lrwxrwxrwx 1 me me 3 May 13 12:00 b -> ./a
a is a text file containing the six bytes 'hello\n'. b is a link file containing the three bytes to its target path: './a'. ls is able to describe the properties of the link without dereferencing the link itself.
In contrast, use the -L option:
$ ls -lL
-rw-rw-r-- 1 me me 6 May 13 11:58 a
-rw-rw-r-- 1 me me 6 May 13 11:58 b
Now ls has resolved the link in b, and displays information about the linked-to file. With -L, ls now claims that b is also a six-byte text file.
Finally, consider this:
$ rm a
$ ls -l
lrwxrwxrwx 1 me me 3 May 13 12:00 b -> ./a
$ ls -lL
ls: cannot access b: No such file or directory
l????????? ? ? ? ? ? b
Now b is a link that resolves to a file that no longer exists. Since ls -l never attempts the resolve the link, its output is unchanged from the previous test. (b is a link file, 3 bytes long, contents './a'.)
But ls -lL attempts to resolve the link, fails, and displays the failure information.