Check File Permissions

Checking File Permissions in Linux with Python

You're right that os.access, like the underlying access syscall, checks for a specific user (real rather than effective IDs, to help out with suid situations).

os.stat is the right way to get more general info about a file, including permissions per user, group, and others. The st_mode attribute of the object that os.stat returns has the permission bits for the file.

To help interpret those bits, you may want to use the stat module. Specifically, you'll want the bitmasks defined here, and you'll use the & operator (bit-and) to use them to mask out the relevant bits in that st_mode attribute -- for example, if you just need a True/False check on whether a certain file is group-readable, one approach is:

import os
import stat

def isgroupreadable(filepath):
  st = os.stat(filepath)
  return bool(st.st_mode & stat.S_IRGRP)

Take care: the os.stat call can be somewhat costly, so make sure to extract all info you care about with a single call, rather than keep repeating calls for each bit of interest;-).

check file permission in javascript

You can't.

That kind of metadata isn't an intrinsic part of the file (unlike, for instance, its size) and depends on the operating systems file permissions system.

The cross-platform File API provided by browsers doesn't implement anything that would give you any of that information.

Checking windows file permissions

The only way to be sure if an operation will succeed is to actually try the operation.

However, SetCurrentDirectory will fail if you don't have FILE_TRAVERSE or SYNCHRONIZE permissions for the folder in question. So you can test this using CreateFile without actually changing the directory.

bool TestForSetCurrentDirPermission(LPCWSTR pszDir)
{
    HANDLE hDir = CreateFile(pszDir, FILE_TRAVERSE | SYNCHRONIZE,
        FILE_SHARE_READ | FILE_SHARE_WRITE, 0, OPEN_EXISTING,
        FILE_FLAG_BACKUP_SEMANTICS, NULL);

    if (hDir != INVALID_HANDLE_VALUE) CloseHandle(hDir);
    return hDir != INVALID_HANDLE_VALUE;
}

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