Namespaces
Variants
Views
Actions

std::experimental::filesystem::space

From cppreference.com
< cpp‎ | experimental‎ | fs
 
 
Technical specifications
Filesystem library (filesystem TS)
Library fundamentals (library fundamentals TS)
Library fundamentals 2 (library fundamentals 2 TS)
Extensions for parallelism (parallelism TS)
Extensions for concurrency (concurrency TS)
Concepts (concepts TS)
Ranges (ranges TS)
Special mathematical functions (special math TR)
 
 
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<uintmax_t>(-1)

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

Contents

[edit] Parameters

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

[edit] Return value

The filesystem information (a space_info object)

[edit] Exceptions

The overload that does not take a 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 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
  

[edit] Notes

space_info.available may be less than space_info.free

[edit] Example

#include <iostream>
#include <experimental/filesystem>
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

[edit] See also

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