https://tanguy.ortolo.eu/blog/article48/everything-file en a blog about Debian and self-hosting Tue, 17 Apr 2012 22:41:00 +0000 PluXml https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334702518-1 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334702518-1 Nope, there are plenty of things that you cannot open(2): sockets, certain types of pipes, certain types of devices. Some interfaces have specific and unusual semantics for open(2), such as named sockets. Some devices don't support read/write. Some socket drivers don't support them either under certain conditions. Many things don't support mmap(2). As I said originally, the only thing that's universally supported is close(2). Only the most basic I/O code can be written without considering what I/O interfaces will be involved. Tue, 17 Apr 2012 22:41:00 +0000 Adam Skutt https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334695638-1 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334695638-1 I am using “dd of=/dev/stdout if=/dev/zero foo=bar” all the time! ;) Tue, 17 Apr 2012 20:47:00 +0000 Jakob https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334695151-1 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334695151-1 > "Everything is a file" is the biggest lie of Unix. Please, could you explain, more precisely? Everything can be opened, read and written so, IMHO, yes, everything is a file. Cheers. Tue, 17 Apr 2012 20:39:00 +0000 Tranxene50 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334689809-1 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334689809-1 "Everything is a file" is the biggest lie of Unix. Take a closer look at Plan 9. Tue, 17 Apr 2012 19:10:00 +0000 9fan https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334660629-1 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334660629-1 @Eddi : No it is not. /dev/std* do exist and they are symlinks to /proc/self/sd*, where /proc/self is itself a symlink to the current process. So in fact, /dev/stdin points to /proc/PID/fd/0. When that process was launched without a redirection, this is a symlink to the corresponding terminal device, for instance /dev/tty1 or /dev/pts/1. When it was launched with a file redirection it is a symlink to that file, and when it was launched in a pipeline it is a symlink to some kind of pipe identifier. Tue, 17 Apr 2012 11:03:00 +0000 Tanguy https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334658616-1 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334658616-1 But, as it seems, this handling of /dev/stdin is a Bash feature! Maybe other shells (Zsh comes to mind) support that too. Tue, 17 Apr 2012 10:30:00 +0000 Eddi https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334621157-1 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334621157-1 I love this! Saving the idea for later for when a second dash on the parameter won't switch to STDIN! Tue, 17 Apr 2012 00:05:00 +0000 Stan Schwertly https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334604922-1 https://tanguy.ortolo.eu/blog/article48/everything-file/#c1334604922-1 Except everything isn't a file. You can't seek pipes or sockets. You can't do select/poll based non-blocking I/O on actual files on disk. The only common operation supported by everything is close(2). And while most applications should probably support I/O operations from stdin to stdout, it's just not feasible for all operating modes of several key UNIX applications like sort(1) and join(1). Windows NT does the "Everything is a handle" thing much better since it has actual support for polymorphic handles, though it still has a considerable number of warts. Mon, 16 Apr 2012 19:35:00 +0000 Adam Skutt