c++ - Combination of std::ios::openmode to truncate if the file exists but prevent new file creation? -


i have asked earlier if there combination of openmode avoid modifications of existing file. know if contrary possible :

  1. if file exists, truncate (std::ios::trunc)
  2. if file not exist, nothing

is there std::ios::openmode available std::ofstream?

to best of knowledge, there no such open mode (it not common use case). guess first check whether file exists and, if does, open trunc open mode.


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