Remove support for FIFOs and pipes.

Now that our sockets API is very simple, there is no added value in
having a separate pipe type. Let's just adjust pipe() to return a socket
pair and alias S_ISPIPE() and S_ISSOCK().

cloudabi.txt

@@ -368,8 +368,7 @@ flags uint16 eventrwflags
 	| [eventtype.fd_read] or [eventtype.fd_write].
 	@cprefix EVENT_FD_READWRITE_
 	0x01 hangup
-		| The peer of this FIFO or socket has closed or
-		| disconnected.
+		| The peer of this socket has closed or disconnected.
 
 enum uint8 eventtype
 	| Type of a subscription to an event or its occurrence.
@@ -483,9 +482,6 @@ enum uint8 filetype
 	0x20 directory
 		| The file descriptor or file refers to a directory
 		| inode.
-	0x30 fifo
-		| The file descriptor or file refers to a FIFO inode or
-		| one of the two endpoints of a pipe.
 	0x40 poll
 		| The file descriptor refers to a polling event queue.
 	0x50 process
@@ -664,9 +660,6 @@ flags uint64 rights
 	0x0000000000000400 file_create_file
 		| If [rights.file_open] is set, the right to invoke
 		| [file_open] with [oflags.creat].
-	0x0000000000000800 file_create_fifo
-		| The right to invoke [file_create] with
-		| [filetype.fifo].
 	0x0000000000001000 file_link_source
 		| The right to invoke [file_link] with the file
 		| descriptor as the source directory.
@@ -1351,20 +1344,16 @@ syscall fd_create2
 	| Creates a pair of file descriptors.
 	in
 		filetype type
-			fifo
-				| Creates a pipe.
 			socket_dgram
 				| Creates a UNIX datagram socket pair.
 			socket_stream
 				| Creates a UNIX byte-stream socket
 				| pair.
 	out
 		fd       fd1
-			| The first file descriptor of the pair. For
-			| pipes, this corresponds to the read end.
+			| The first file descriptor of the pair.
 		fd       fd2
-			| The second file descriptor of the pair. For
-			| pipes, this corresponds to the write end.
+			| The second file descriptor of the pair.
 
 syscall fd_datasync
 	| Synchronizes the data of a file to disk.
@@ -1547,8 +1536,6 @@ syscall file_create
 		filetype    type
 			directory
 				| Creates a directory.
-			fifo
-				| Creates a FIFO.
 
 syscall file_link
 	| Creates a hard link.

docs/cloudabi.html

@@ -402,9 +402,6 @@ <h4><a href="#fd_create2" name="fd_create2"></a><code>cloudabi_sys_fd_create2()<
 <p>Possible values:</p>
 
 <ul>
-<li><p><a href="#filetype.fifo"><code>CLOUDABI_FILETYPE_FIFO</code></a></p>
-
-<p>Creates a pipe.</p></li>
 <li><p><a href="#filetype.socket_dgram"><code>CLOUDABI_FILETYPE_SOCKET_DGRAM</code></a></p>
 
 <p>Creates a UNIX datagram socket pair.</p></li>
@@ -420,12 +417,10 @@ <h4><a href="#fd_create2" name="fd_create2"></a><code>cloudabi_sys_fd_create2()<
 <ul>
 <li><p><a href="#fd_create2.fd1" name="fd_create2.fd1"></a><code><a href="#fd">cloudabi_fd_t</a> <strong>fd1</strong></code></p>
 
-<p>The first file descriptor of the pair. For
-pipes, this corresponds to the read end.</p></li>
+<p>The first file descriptor of the pair.</p></li>
 <li><p><a href="#fd_create2.fd2" name="fd_create2.fd2"></a><code><a href="#fd">cloudabi_fd_t</a> <strong>fd2</strong></code></p>
 
-<p>The second file descriptor of the pair. For
-pipes, this corresponds to the write end.</p></li>
+<p>The second file descriptor of the pair.</p></li>
 </ul>
 
 <h4><a href="#fd_datasync" name="fd_datasync"></a><code>cloudabi_sys_fd_datasync()</code></h4>
@@ -745,9 +740,6 @@ <h4><a href="#file_create" name="file_create"></a><code>cloudabi_sys_file_create
 <li><p><a href="#filetype.directory"><code>CLOUDABI_FILETYPE_DIRECTORY</code></a></p>
 
 <p>Creates a directory.</p></li>
-<li><p><a href="#filetype.fifo"><code>CLOUDABI_FILETYPE_FIFO</code></a></p>
-
-<p>Creates a FIFO.</p></li>
 </ul></li>
 </ul>
 
@@ -2072,8 +2064,7 @@ <h4><a href="#eventrwflags" name="eventrwflags"></a><code>cloudabi_eventrwflags_
 <ul>
 <li><p><a href="#eventrwflags.hangup" name="eventrwflags.hangup"></a><strong><code>CLOUDABI_EVENT_FD_READWRITE_HANGUP</code></strong></p>
 
-<p>The peer of this FIFO or socket has closed or
-disconnected.</p></li>
+<p>The peer of this socket has closed or disconnected.</p></li>
 </ul>
 
 <h4><a href="#eventtype" name="eventtype"></a><code>cloudabi_eventtype_t</code> (<code>uint8_t</code>)</h4>
@@ -2294,10 +2285,6 @@ <h4><a href="#filetype" name="filetype"></a><code>cloudabi_filetype_t</code> (<c
 
 <p>The file descriptor or file refers to a directory
 inode.</p></li>
-<li><p><a href="#filetype.fifo" name="filetype.fifo"></a><strong><code>CLOUDABI_FILETYPE_FIFO</code></strong></p>
-
-<p>The file descriptor or file refers to a FIFO inode or
-one of the two endpoints of a pipe.</p></li>
 <li><p><a href="#filetype.poll" name="filetype.poll"></a><strong><code>CLOUDABI_FILETYPE_POLL</code></strong></p>
 
 <p>The file descriptor refers to a polling event queue.</p></li>
@@ -2698,10 +2685,6 @@ <h4><a href="#rights" name="rights"></a><code>cloudabi_rights_t</code> (<code>ui
 
 <p>If <a href="#rights.file_open"><code>CLOUDABI_RIGHT_FILE_OPEN</code></a> is set, the right to invoke
 <a href="#file_open"><code>cloudabi_sys_file_open()</code></a> with <a href="#oflags.creat"><code>CLOUDABI_O_CREAT</code></a>.</p></li>
-<li><p><a href="#rights.file_create_fifo" name="rights.file_create_fifo"></a><strong><code>CLOUDABI_RIGHT_FILE_CREATE_FIFO</code></strong></p>
-
-<p>The right to invoke <a href="#file_create"><code>cloudabi_sys_file_create()</code></a> with
-<a href="#filetype.fifo"><code>CLOUDABI_FILETYPE_FIFO</code></a>.</p></li>
 <li><p><a href="#rights.file_link_source" name="rights.file_link_source"></a><strong><code>CLOUDABI_RIGHT_FILE_LINK_SOURCE</code></strong></p>
 
 <p>The right to invoke <a href="#file_link"><code>cloudabi_sys_file_link()</code></a> with the file

docs/cloudabi.md

@@ -273,10 +273,6 @@ Inputs:
 
     Possible values:
 
-    - [`CLOUDABI_FILETYPE_FIFO`](#filetype.fifo)
-
-        Creates a pipe.
-
     - [`CLOUDABI_FILETYPE_SOCKET_DGRAM`](#filetype.socket_dgram)
 
         Creates a UNIX datagram socket pair.
@@ -290,13 +286,11 @@ Outputs:
 
 - <a href="#fd_create2.fd1" name="fd_create2.fd1"></a><code>[cloudabi\_fd\_t](#fd) <strong>fd1</strong></code>
 
-    The first file descriptor of the pair. For
-    pipes, this corresponds to the read end.
+    The first file descriptor of the pair.
 
 - <a href="#fd_create2.fd2" name="fd_create2.fd2"></a><code>[cloudabi\_fd\_t](#fd) <strong>fd2</strong></code>
 
-    The second file descriptor of the pair. For
-    pipes, this corresponds to the write end.
+    The second file descriptor of the pair.
 
 #### <a href="#fd_datasync" name="fd_datasync"></a>`cloudabi_sys_fd_datasync()`
 
@@ -595,10 +589,6 @@ Inputs:
 
         Creates a directory.
 
-    - [`CLOUDABI_FILETYPE_FIFO`](#filetype.fifo)
-
-        Creates a FIFO.
-
 #### <a href="#file_link" name="file_link"></a>`cloudabi_sys_file_link()`
 
 Creates a hard link.
@@ -1959,8 +1949,7 @@ Possible values:
 
 - <a href="#eventrwflags.hangup" name="eventrwflags.hangup"></a>**`CLOUDABI_EVENT_FD_READWRITE_HANGUP`**
 
-    The peer of this FIFO or socket has closed or
-    disconnected.
+    The peer of this socket has closed or disconnected.
 
 #### <a href="#eventtype" name="eventtype"></a>`cloudabi_eventtype_t` (`uint8_t`)
 
@@ -2193,11 +2182,6 @@ Possible values:
     The file descriptor or file refers to a directory
     inode.
 
-- <a href="#filetype.fifo" name="filetype.fifo"></a>**`CLOUDABI_FILETYPE_FIFO`**
-
-    The file descriptor or file refers to a FIFO inode or
-    one of the two endpoints of a pipe.
-
 - <a href="#filetype.poll" name="filetype.poll"></a>**`CLOUDABI_FILETYPE_POLL`**
 
     The file descriptor refers to a polling event queue.
@@ -2611,11 +2595,6 @@ Possible values:
     If [`CLOUDABI_RIGHT_FILE_OPEN`](#rights.file_open) is set, the right to invoke
     [`cloudabi_sys_file_open()`](#file_open) with [`CLOUDABI_O_CREAT`](#oflags.creat).
 
-- <a href="#rights.file_create_fifo" name="rights.file_create_fifo"></a>**`CLOUDABI_RIGHT_FILE_CREATE_FIFO`**
-
-    The right to invoke [`cloudabi_sys_file_create()`](#file_create) with
-    [`CLOUDABI_FILETYPE_FIFO`](#filetype.fifo).
-
 - <a href="#rights.file_link_source" name="rights.file_link_source"></a>**`CLOUDABI_RIGHT_FILE_LINK_SOURCE`**
 
     The right to invoke [`cloudabi_sys_file_link()`](#file_link) with the file

headers/cloudabi_types_common.h

@@ -191,7 +191,6 @@ typedef uint8_t cloudabi_filetype_t;
 #define CLOUDABI_FILETYPE_BLOCK_DEVICE      16
 #define CLOUDABI_FILETYPE_CHARACTER_DEVICE  17
 #define CLOUDABI_FILETYPE_DIRECTORY         32
-#define CLOUDABI_FILETYPE_FIFO              48
 #define CLOUDABI_FILETYPE_POLL              64
 #define CLOUDABI_FILETYPE_PROCESS           80
 #define CLOUDABI_FILETYPE_REGULAR_FILE      96
@@ -260,7 +259,6 @@ typedef uint64_t cloudabi_rights_t;
 #define CLOUDABI_RIGHT_FILE_ALLOCATE         0x0000000000000100
 #define CLOUDABI_RIGHT_FILE_CREATE_DIRECTORY 0x0000000000000200
 #define CLOUDABI_RIGHT_FILE_CREATE_FILE      0x0000000000000400
-#define CLOUDABI_RIGHT_FILE_CREATE_FIFO      0x0000000000000800
 #define CLOUDABI_RIGHT_FILE_LINK_SOURCE      0x0000000000001000
 #define CLOUDABI_RIGHT_FILE_LINK_TARGET      0x0000000000002000
 #define CLOUDABI_RIGHT_FILE_OPEN             0x0000000000004000