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Why Isn\'t My `std::fstream` Creating a File?

Patricia Arquette

Nov 02, 2024 pm 07:54 PM

Why Isn't My `std::fstream` Creating a File?

std::fstream Not Creating File?

When attempting to use std::fstream for I/O operations on a file, you may encounter an issue where the file is not created if it doesn't already exist.

This is often caused by specifying std::fstream::in as a mode in fstream::open(). This flag restricts the file stream to reading from an existing file, prohibiting the creation of a new one.

To resolve the issue and enable file creation when necessary, consider the following options:

Remove std::fstream::in from the mode argument: This will allow the file stream to create a new file if it doesn't exist.
Specify std::fstream::trunc in addition to other flags: This flag will truncate the file if it exists and create a new one if it doesn't.

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