Replace file using std::filesystem

Question

Often there is a pattern

of writing an output to temporary file(bla.txt.tmp)
deleting the original (rm bla.txt)
renaming a new one(bla.txt.tmp -> bla.txt)

Is there any utility function in std::filesystem to do this or I need to do steps one by one using rename and remove.

Why can't you just open the file and directly replace it's contents? — NathanOliver, Sep 13 '19 at 15:59
@NathanOliver OP's pattern is actually very common as a way to avoid incomplete writes caused by system failure or program error. — Xirema, Sep 13 '19 at 16:00

score 4 · Accepted Answer · answered Sep 13 '19 at 16:02

No. There is no such utility function in the standard library. Each step can be done with std::filesystem though and you can write such utility function yourself.

std::filesystem::rename does perform both steps 2. and 3. in one call, but creating the new file must be done separately.

Replace file using std::filesystem

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