CODEWITHSUNDEEP
ed
Andrea Monaco
Andrea Monaco

Reputation: 79

Temporary file deleted

I'm working on ed (yes, the editor) source code. The program uses a scratch file, opened with tmpfile, as a buffer. But, whenever I run the program, lsof always report the temporary file as deleted! (and in fact it's not there). Why?

Upvotes: 2

Views: 85

Answers (1)

Gumnos
Gumnos

Reputation: 423

Because a file can exist on disk without having a filename associated with it, many programs will open a file and then promptly unlink it. The file contents can continue to be modified & read by open file-handles on the file, and won't actually be removed from the disk until all open file handles are closed.

(this is for *nix/POSIX platforms AFAICT; Windows handles files differently, preventing unlinking if an program has the file-handle still open, and thus reboots are often needed for upgrades to force those open file-handles to be closed so file contents can be replaced)

Upvotes: 0

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