std::filesystem::absolute

 

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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::file_time_type filesystem::perms filesystem::perm_options filesystem::copy_options filesystem::directory_options
Functions
filesystem::absolute filesystem::canonicalfilesystem::weakly_canonical filesystem::relativefilesystem::proximate 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::temp_directory_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
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 <filesystem>
path absolute(conststd::filesystem::path& p );	(1)	(since C++17)
path absolute(conststd::filesystem::path& p, std::error_code& ec );	(2)	(since C++17)

Returns a path referencing the same file system location as p, for which filesystem::path::is_absolute() is true.

2) This non-throwing overload returns default-constructed path if an error occurs.

Parameters

p	-	path to convert to absolute form
ec	-	out-parameter for error reporting in the non-throwing overload

Return value

Returns an absolute (although not necessarily canonical) pathname referencing the same file as p.

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 p 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.

Notes

Implementations are encouraged to not consider p not existing to be an error.

For POSIX-based operating systems, std::filesystem::absolute(p) is equivalent to std::filesystem::current_path()/ p except for when p is the empty path.

For Windows, std::filesystem::absolute may be implemented as a call to GetFullPathNameW.

Example

Run this code

#include <filesystem>#include <iostream>namespace fs = std::filesystem;   int main(){std::filesystem::path p ="foo.c";std::cout<<"Current path is "<<std::filesystem::current_path()<<'\n';std::cout<<"Absolute path for "<< p <<" is "<< fs::absolute(p)<<'\n';}

Possible output:

Current path is "/tmp/1666297965.0051296" Absolute path for "foo.c" is "/tmp/1666297965.0051296/foo.c"

See also

canonicalweakly_canonical (C++17)	composes a canonical path (function)
relativeproximate (C++17)	composes a relative path (function)