browser - Why do file URLs start with 3 slashes?

HTTP starts with two slashes. E.g. http://example.com.

Same goes for FTP. E.g. ftp://example.com.

However, file "URLs" start with three slashes. E.g. Reading a pdf file using chrome, the URL would be file:///D:/Desktop/Book.pdf.

Why do file URLs use three slashes?

Answer

As others have mentioned, the file schema is in the form "file:///". Though most browsers won't have a problem with only two slashes, and rightfully so.

All things being equal, the triple slash and "localhost" keyword only exist to ensure conformance with valid URI/URL syntax. In the context of the file schema, the host is meaningless since it loads directly from a filesystem without any explicit transfer protocol or server document path. Because it's not HTTP, it can't load from a standard web server where in theory you could have multiple local virtual hosts set up. And it can't load from a standard network volume that's technically another "host", since the browser just uses the volume name like "file:///volumes/foo". Finally, trying things like "file://example.com/some/file" doesn't work. There's probably some reason for supporting an external host, but I can't think of any.

The IETF is currently drafting changes to remove the triple-slash requirement, though the draft also adds a few oddball possibilities like file:c|/path and even file://///host.example.com/path.

https://tools.ietf.org/html/draft-ietf-appsawg-file-scheme-03

"3. This specification neither defines nor forbids a mechanism for accessing non-local files."

Comments

Use Google instead of Bing with Windows 10 search

I want to use Google Chrome and Google search instead of Bing when I search in Windows 10. Google Chrome is launched when I click on web, but it's Bing search. (My default search engine on Google and Edge is http://www.google.com ) I haven't found how to configure that. Someone can help me ? Answer There is no way to change the default in Cortana itself but you can redirect it in Chrome. You said that it opens the results in the Chrome browser but it used Bing search right? There's a Chrome extension now that will redirect Bing to Google, DuckDuckGo, or Yahoo , whichever you prefer. More information on that in the second link.

linux - Using an index to make grep faster?

I find myself grepping the same codebase over and over. While it works great, each command takes about 10 seconds, so I am thinking about ways to make it faster. So can grep use some sort of index? I understand an index probably won't help for complicated regexps, but I use mostly very simple patters. Does an indexer exist for this case? EDIT: I know about ctags and the like, but I would like to do full-text search. Answer what about cscope , does this match your shoes? Allows searching code for: all references to a symbol global definitions functions called by a function functions calling a function text string regular expression pattern a file files including a file

How do I transmit a single hexadecimal value serial data in PuTTY using an Alt code?

I am trying to sent a specific hexadecimal value across a serial COM port using PuTTY. Specifically, I want to send the hex codes 9C, B6, FC, and 8B. I have looked up the Alt codes for these and they are 156, 182, 252, and 139 respectively. However, whenever I input the Alt codes, a preceding hex value of C2 is sent before 9C, B6, and 8B so the values that are sent are C2 9C, C2 B6, and C2 8B. The value for FC is changed to C3 FC. Why are these values being placed before the hex value and why is FC being changed altogether? To me, it seems like there is a problem internally converting the Alt code to hex. Is there a way to directly input hex values without using Alt codes in PuTTY? Answer What you're seeing is just ordinary text character set conversion. As far as PuTTY is concerned, you are typing (and reading) text , not raw binary data, therefore it has to convert the text to bytes in whatever configured character set before sending it over the wire. In other words, when y

networking - Windows 10, can ping other PC but cannot access shared folders! What gives?

I have a computer running Windows 7 that shares a Git repo on drive D. Let's call this PC " win7 ". This repo is the origin of a project that we push to and pull from. The network is a wireless network. One PC on this network is running on Windows 10. Let's call this PC " win10 ". Win10 can ping every other PC on the network including win7 . Win7 can ping win10 . Win7 can access all shared files on win10 . Neither of the PCs have passwords. Problem : Win10 cannot access any shared files on win7 , not from Explorer, nor from Git Bash or any other Git management system (E-Git on Eclipse or Visual Studio). So, win10 cannot pull/push. Every other PC on the network can access win7 shared files and push/pull to/from the shared Git origin. What's wrong with Windows 10? I have tried these: Control Panel\All Control Panel Items\Network and Sharing Center\Advanced sharing settings\ File sharing is on, Discovery is on, Password protected sharing is off Adapte

Notes

Search This Blog