Re: [PATCH] fchmodat, lchmod: port to buggy Linux filesystems

[Bruno Haible]

The original thread's subject "XFS reports lchmod failure, but changes
file system contents" gave the impression that it's somehow XFS specific.

But what I observe is that the behaviour is the same on all major file
systems on Linux.

Tested on Linux 5.3.7 (fc31), with the trivial program below, on
  - ext4
  - btrfs
  - jfs
  - reiserfs
  - xfs
Before your latest patch: mode changed, but error "Operation not supported".
After  your latest patch: mode not changed, error "Operation not supported".

Bruno


============================ lchmod.c ============================
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
int main (int argc, char *argv[])
{
        int mode = strtol (argv[1], NULL, 8);
        char *path = argv[2];
        int ret = lchmod (path, mode);
        if (ret < 0)
                perror ("lchmod");
}