std::experimental::filesystem::space

 

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Filesystem library

Classes
filesystem::path filesystem::filesystem_error filesystem::directory_entry filesystem::directory_iterator filesystem::recursive_directory_iterator filesystem::file_status	filesystem::space_info filesystem::file_type filesystem::perms filesystem::copy_options filesystem::directory_options filesystem::file_time_type
Functions
filesystem::absolute filesystem::system_complete filesystem::canonical filesystem::copy filesystem::copy_file filesystem::copy_symlink filesystem::create_directory filesystem::create_directories filesystem::create_hard_link filesystem::create_symlink filesystem::create_directory_symlink filesystem::current_path filesystem::exists filesystem::equivalent	filesystem::file_size filesystem::hard_link_count filesystem::last_write_time filesystem::permissions filesystem::read_symlink filesystem::remove filesystem::remove_all filesystem::rename filesystem::resize_file filesystem::space filesystem::status filesystem::symlink_status filesystem::temp_directory_path
File types
filesystem::is_block_file filesystem::is_character_file filesystem::is_directory filesystem::is_empty filesystem::status_known	filesystem::is_fifo filesystem::is_other filesystem::is_regular_file filesystem::is_socket filesystem::is_symlink

 

Defined in header <experimental/filesystem>
space_info space( const path& p ); space_info space( const path& p, error_code& ec ) noexcept;		(filesystem TS)

Determines the information about the filesystem on which the pathname p is located, as if by POSIX statvfs.

Populates and returns an object of type space_info, set from the members of the POSIX struct statvfs as follows:

• space_info.capacity is set as if by f_blocks * f_frsize.
• space_info.free is set to f_bfree * f_frsize.
• space_info.available is set to f_bavail * f_frsize.
• Any member that could not be determined is set to static_cast<std::uintmax_t>(-1).

The non-throwing overload sets all members to static_cast<std::uintmax_t>(-1) on error.

Parameters

p	-	path to examine
ec	-	out-parameter for error reporting in the non-throwing overload

Return value

The filesystem information (a space_info object).

Exceptions

The overload that does not take an error_code& parameter throws filesystem_error on underlying OS API errors, constructed with p 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 an 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

space_info.available may be less than space_info.free.

Example

Run this code

#include <experimental/filesystem>
#include <iostream>
namespace fs = std::experimental::filesystem;
 
int main()
{
    fs::space_info devi = fs::space("/dev/null");
    fs::space_info tmpi = fs::space("/tmp");
 
    std::cout << "         Capacity         Free    Available\n"
              << "/dev:   " << devi.capacity << "   "
              << devi.free << "   " << devi.available << '\n'
              << "/tmp: " << tmpi.capacity << ' '
              << tmpi.free << ' ' << tmpi.available << '\n';
}

Possible output:

          Capacity         Free    Available
/dev:   4175114240   4175110144   4175110144
/tmp: 420651237376 411962273792 390570749952

See also

space_info

information about free and available space on the filesystem (class)