std::experimental::filesystem::path::compare

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Filesystem library(C++17)
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Experimental

Technical Specification
Filesystem library(filesystem TS)
Library fundamentals(library fundamentals TS)
Library fundamentals 2(library fundamentals TS v2)
Library fundamentals 3(library fundamentals TS v3)
Extensions for parallelism(parallelism TS)
Extensions for parallelism 2(parallelism TS v2)
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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

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path

Member functions

path::path
path::~path
path::operator=
path::assign
path::appendoperator /=
path::concatoperator +=
path::clear
path::make_preferred
path::remove_filename
path::replace_filename
path::replace_extension
path::swap
path::compare

path::c_strpath::nativeoperator string_type
path::stringpath::u8stringpath::u16stringpath::u32stringpath::wstring
path::generic_stringpath::generic_u8stringpath::generic_u16stringpath::generic_u32stringpath::generic_wstring
path::beginpath::end

Path decomposition

path::root_name
path::root_directory
path::root_path
path::relative_path
path::parent_path
path::filename
path::stem
path::extension
path::empty

path::has_root_pathpath::has_root_namepath::has_root_directorypath::has_relative_pathpath::has_parent_pathpath::has_filenamepath::has_stempath::has_extension
path::is_absolutepath::is_relative

Non-member functions

swap(path)

operator==operator!=operator<operator<=operator>operator>=

int compare(const path& p)constnoexcept;	(1)	(filesystem TS)
int compare(const string_type& str)const;	(2)	(filesystem TS)
int compare(const value_type* s)const;	(3)	(filesystem TS)

Compares the lexical representations of the path and another path.

1) Returns a value less than, equal to or greater than0 if the native representation of the path (native()) is respectively lexicographically less than, equal to or greater than the native representation ofp (p.native()). Comparison is performed element-wise, as if by iterating both paths frombegin() toend().

2) Equivalent tocompare(path(str)).

3) Equivalent tocompare(path(s)).

[edit]Parameters

p	-	a path to compare to
str	-	a string representing path to compare to
s	-	a null-terminated string representing path to compare to

[edit]Return value

A value less than0 if the path is lexicographically less than the given path.

A value equal to0 if the path is lexicographically equal to the given path.

A value greater than0 if the path is lexicographically greater than the given path.

[edit]Exceptions

2,3) May throw implementation-defined exceptions.

[edit]Notes

For two-way comparisons,binary operators may be more suitable.

[edit]Example

Run this code

#include <experimental/filesystem>#include <iostream>namespace fs= std::experimental::filesystem; void demo(int rc, fs::path p1, fs::path p2){if(rc<0)std::cout<< p1<<" < "<< p2<<'\n';elseif(rc>0)std::cout<< p1<<" > "<< p2<<'\n';elseif(rc==0)std::cout<< p1<<" = "<< p2<<'\n';} int main(){    fs::path p1="/a/b/";// as if "a/b/." for lexicographical iteration    fs::path p2="/a/b/#";    demo(p1.compare(p2), p1, p2);    demo(p1.compare("a/b/_"), p1,"a/b/_");}