std::experimental::filesystem::temp_directory_path

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Technical specifications
Filesystem library (filesystem TS)
Library fundamentals (library fundamentals TS)
Library fundamentals 2 (library fundamentals 2 TS)
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Extensions for parallelism 2 (parallelism TS v2)
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Defined in header <experimental/filesystem>
path temp_directory_path();
path temp_directory_path( error_code& ec );
(1) (filesystem TS)

Returns the directory location suitable for temporary files.

Parameters

(none)

Return value

A directory suitable for temporary files. The path is guaranteed to exist and to be a directory. The overload that takes error_code& argument returns an empty path on error.

Exceptions

The overload that does not take a error_code& parameter throws filesystem_error on underlying OS API errors, constructed with path to be returned as the first argument and the OS error code as the error code argument. std::bad_alloc may be thrown if memory allocation fails. The overload taking a error_code& parameter sets it to the OS API error code if an OS API call fails, and executes ec.clear() if no errors occur. This overload has
noexcept specification:
noexcept

Notes

On POSIX systems, the path may be the one specified in the environment variables TMPDIR, TMP, TEMP, TEMPDIR, and, if none of them are specified, the path "/tmp" is returned.

On Windows systems, the path is typically the one returned by GetTempPath

Example

#include <iostream>
#include <experimental/filesystem>
namespace fs = std::experimental::filesystem;
int main()
{
    std::cout << "Temp directory is " << fs::temp_directory_path() << '\n';
}

Possible output:

Temp directory is "C:\Windows\TEMP\"

See also

creates and opens a temporary, auto-removing file
(function)