std::filesystem::temp_directory_path
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Filesystem library 
 
 
 
 
 
filesystem::temp_directory_path
Defined in header 
 
 
<filesystem> 
 path temp_directory_path();
 (1) 
 (since C++17) 
path temp_directory_path( std::error_code & ec );
 (2) 
 (since C++17) 
Returns the directory location suitable for temporary files.
[edit] Parameters
(none)
[edit] 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.
[edit] Exceptions
Any overload not marked noexcept may throw std::bad_alloc  if memory allocation fails.
1) Throws std::filesystem::filesystem_error  on underlying OS API errors, constructed with path to be returned as the first path argument and the OS error code as the error code argument.
2) Sets a std::error_code & parameter to the OS API error code if an OS API call fails, and executes ec.clear () if no errors occur.
[edit] 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.
[edit] Example
Run this code
#include <filesystem> #include <iostream> namespace fs = std::filesystem; int main() { std::cout << "Temp directory is " << fs::temp_directory_path() << '\n'; }
Possible output:
Temp directory is "C:\Windows\TEMP\"