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Change directory with cd command to the desired location under with you need to all directories to 755, and all files to 644 permissions. Then use first command to chmod 755 for all directories and sub directories. The second command will change all the files permission to 0644 (chmod 644) under the directory tree.
Permissions of 644 mean that the owner of the file has read and write access, while the group members and other users on the system only have read access. Issue one of the following chmod commands to reset the permissions on a file back to one of the likely defaults: chmod 600 ~/example.txt chmod 644 ~/example.txt.
-rw-r--r-- (644) -- Only user has read and write permissions; the group and others can read only. -rwx------ (700) -- Only the user has read, write and execute permissions. -rwxr-xr-x (755) -- The user has read, write and execute permissions; the group and others can only read and execute.
Some file permission examples: 777 - all can read/write/execute (full access). 755 - owner can read/write/execute, group/others can read/execute. 644 - owner can read/write, group/others can read only.
Found this on a different forum
If you're wondering why that leading zero is important, it's because permissions are set as an octal integer, and Python automagically treats any integer with a leading zero as octal. So os.chmod("file", 484) (in decimal) would give the same result.
What you are doing is passing 664 which in octal is 1230
In your case you would need
os.chmod("/tmp/test_file", 436)
[Update] Note, for Python 3 you have prefix with 0o (zero oh). E.G, 0o666
So for people who want semantics similar to:
$ chmod 755 somefile
Use:
$ python -c "import os; os.chmod('somefile', 0o755)"
If your Python is older than 2.6:
$ python -c "import os; os.chmod('somefile', 0755)"
Use permission symbols (stat.S_I*) instead of raw octal numbers
Your problem would have been avoided if you had used the more semantically named permission symbols rather than raw magic numbers, e.g. for 664:
#!/usr/bin/env python3
import os
import stat
os.chmod(
'myfile',
stat.S_IRUSR |
stat.S_IWUSR |
stat.S_IRGRP |
stat.S_IWGRP |
stat.S_IROTH
)
This is documented at https://docs.python.org/3/library/os.html#os.chmod and the names are the same as the POSIX C API which is also present at man 2 stat and man 2 chmod:
S_IRUSR (00400) read by owner
S_IWUSR (00200) write by owner
S_IXUSR (00100) execute/search by owner
S_IRGRP (00040) read by group
S_IWGRP (00020) write by group
S_IXGRP (00010) execute/search by group
S_IROTH (00004) read by others
S_IWOTH (00002) write by others
S_IXOTH (00001) execute/search by others
Another advantage is the greater portability as mentioned in the docs:
Note: Although Windows supports
chmod(), you can only set the file’s read-only flag with it (via thestat.S_IWRITEandstat.S_IREADconstants or a corresponding integer value). All other bits are ignored.
chmod +x is demonstrated at: How do you do a simple "chmod +x" from within python?
Tested in Ubuntu 16.04, Python 3.5.2.
leading 0 means this is octal constant, not the decimal one. and you need an octal to change file mode.
permissions are a bit mask, for example, rwxrwx--- is 111111000 in binary, and it's very easy to group bits by 3 to convert to the octal, than calculate the decimal representation.
0644 (octal) is 0.110.100.100 in binary (i've added dots for readability), or, as you may calculate, 420 in decimal.
If you have desired permissions saved to string then do
s = '660'
os.chmod(file_path, int(s, base=8))
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