') + ')', 'gi'); if (regex.test(text)) { found = true; var frag = document.createDocumentFragment(); var parts = text.split(regex); parts.forEach(function(part, i) { if (i % 2 === 0) { frag.appendChild(document.createTextNode(part)); } else { var span = document.createElement('span'); span.className = 'userscript-highlight'; span.textContent = part; frag.appendChild(span); } }); node.parentNode.replaceChild(frag, node); } }); } else if (node.nodeType === 1 && node.childNodes) { // element var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT']; if (!skipTags.includes(node.tagName)) { Array.from(node.childNodes).forEach(highlight); } } } highlight(document.body); // Re-highlight on dynamic content var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1 || node.nodeType === 3) highlight(node); }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Strip utm_, fbclid, gclid, etc. from all links on page (function() { var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content', 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid', 'ref', 'ref_src', 'source', 'medium', 'campaign']; function cleanUrl(url) { try { var u = new URL(url, window.location.origin); var changed = false; trackingParams.forEach(function(p) { if (u.searchParams.has(p)) { u.searchParams.delete(p); changed = true; } }); return changed ? u.toString() : url; } catch (e) { return url; } } function cleanLinks() { document.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } cleanLinks(); var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1) { if (node.tagName === 'A') cleanLinks(); node.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Auto-enable theater mode on YouTube (function() { function tryTheater() { var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]'); if (btn && !btn.classList.contains('activated')) { btn.click(); } } // Try immediately tryTheater(); // Try after navigation (SPA) var lastUrl = location.href; setInterval(function() { if (location.href !== lastUrl) { lastUrl = location.href; setTimeout(tryTheater, 500); } }, 1000); // Also try on player load var observer = new MutationObserver(tryTheater); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Remove or un-stick sticky/fixed headers that block content (function() { function unstick() { document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) { if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') { el.style.position = 'static'; el.style.top = 'auto'; el.style.zIndex = 'auto'; } }); } unstick(); var observer = new MutationObserver(unstick); observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] }); })(); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); })(); Add API to access "extended file attributes" (xattr, EA) · Issue #49604 · dotnet/runtime · GitHub
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Add API to access "extended file attributes" (xattr, EA) #49604

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Add API to access "extended file attributes" (xattr, EA)#49604
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api-suggestionEarly API idea and discussion, it is NOT ready for implementationarea-System.IOneeds-further-triageIssue has been initially triaged, but needs deeper consideration or reconsideration
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Future

Description

@heinrich-ulbricht
heinrich-ulbricht
opened on Mar 14, 2021

Background and Motivation

The API currently lacks support to create, read, update and delete "extended file attributes". What are extended file attributes? Citation from the Wikipedia article:

Extended file attributes are file system features that enable users to associate computer files with metadata not interpreted by the filesystem, whereas regular attributes have a purpose strictly defined by the filesystem (such as permissions or records of creation and modification times).

On *nix based systems they are called xattr, on Windows E xtended A ttributes (EA).

MacOS documentation: https://ss64.com/osx/xattr.html
Linux documentation: https://man7.org/linux/man-pages/man7/xattr.7.html
Windows documentation (?): https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-fscc/a82e9105-2405-4e37-b2c3-28c773902d85?redirectedfrom=MSDN ($EA and $EA_INFORMATION)
Hints to usage of EA on Windows: https://superuser.com/q/396692/93905

My use case specifically is storing an ID for files that is not visible for the user but links those files to external cloud sources those files were generated (and need to be updated) from. Internet Explorer seems to store the "downloaded from Internet" information there, Antivirus vendors store scan information, Dropbox used those properties in the past as well - there definitely are use cases.

Extended file attributes are a lightweight, cross-platform way of storing file metadata that cannot be tinkered with (at least not easily) by the user. Platform/file system support seems to be good. There are even recent developments like Linux NFS support for xattr: User Xattr Support Finally Landing For NFS In Linux 5.9 To cite one comment: "I've been wanting this for years!" ;)

Proposed API

As extension to System.IO.File?

namespaceSystem.IO{publicstaticclassFile{publicstaticFileExtendedAttributesGetExtendedAttributes(stringpath);}}

(Note: Like the existing File.GetAttributes API)

(Note: It's also possible to set those attributes on directories.)

Usage Examples

try{// here FileExtendedAttributes behaves like a Dictionary<string, string> - although binary values should be possible as wellFileExtendedAttributesextendedAttributes=File.GetExtendedAttributes("Program.cs");extendedAttributes.Add("key","value");Debug.WriteLine(string.Join(", ",extendedAttributes.Keys));// "key"Debug.WriteLine(string.Join(", ",extendedAttributes.Values));// "value"extendedAttributes.Remove("key");}catch(NotSupportedException){// not supported by the underlying platform, file system or kernel}

Alternative Designs

The API design should reflect existing implementations from other languages and/or platforms. If this proposal is deemed worthy of being pursued further then we would have to look deeper into existing designs.

Risks

Effort for a rarely-used (?) feature.

Short-sighted design; searching for files based on those property values could be desirable. How could this be designed in contrast to existing designs?

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