The issue is that you use fcntl to get a byte-level write lock (the lowercase w) while visudo uses flock or lockf (depending on what you have) to lock the whole file (uppercase W). The lowercase u is because visudo opens the file read-write and you open it for append.

HTH, --traveler

In reply to Re: With a fcntl lock, why this lsof output? by traveler
in thread With a fcntl lock, why this lsof output? by welchavw

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