privileges - lsof: WARNING: can't stat() fuse.gvfsd-fuse file system - Unix & Linux Stack Exchange

privileges - lsof: WARNING: can't stat() fuse.gvfsd-fuse file system - Unix & Linux Stack Exchange

FUSE and its access rights

lsof by default checks all mounted file systems including FUSE - file systems implemented in user space which have special access rights in Linux.

As you can see in this answer on Ask Ubuntu a mounted GVFS file system (special case of FUSE) is normally accessible only to the user which mounted it (the owner of gvfsd-fuse). Even root cannot access it. To override this restriction it is possible to use mount options allow_root and allow_other. The option must be also enabled in the FUSE daemon which is described for example in this answer ...but in your case you do not need to (and should not) change the access rights.

Excluding file systems from lsof

In your case lsof does not need to check the GVFS file systems so you can exclude the stat() calls on them using the -e option (or you can just ignore the waring):

lsof -e /run/user/1000/gvfs  

Checking certain files by lsof

You are using lsof to get information about all processes running on your system and only then you filter the complete output using grep. If you want to check just certain files and the related processes use the -f option without a value directly following it then specify a list of files after the "end of options" separator --. This will be considerably faster.

lsof -e /run/user/1000/gvfs -f -- /tmp/report.csv  

General solution

To exclude all mounted file systems on which stat() fails you can run something like this (in bash):

x=(); for a in $(mount | cut -d' ' -f3); do test -e "$a" || x+=("-e$a"); done  lsof "${x[@]}" -f -- /tmp/report.csv

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