[PATCH] man page update

diff --git a/splice.2 b/splice.2
index e8a531452be99bbcfbf2123a0fc0f61985f1ffc9..ad0ac9a47bae5efad7baaf98b73f400bca000dd0 100644 (file)
--- a/splice.2
+++ b/splice.2
@@ -10,7 +10,8 @@ splice \- splice data to/from a pipe.
 The act of splicing can be seen as a way to connect two ends of a rope
 through a kernel buffer, where that buffer is implemented as a pipe. It
 provides a means to move data around without copying it to/from kernel/user
-address space.
+address space, basically a random kernel buffer that the user has full
+control over.
 
 The
 .BR splice ()
@@ -37,7 +38,7 @@ Do not block on io.
 More data will be coming in a subsequent splice. This is a helpful hint when
 the output descriptor refers to a socket, see also
 .B MSG_MORE
-(see 
+(see
 .BR send (2)
 and
 .B TCP_CORK
@@ -63,6 +64,9 @@ File descriptors either not valid, or do not have proper rw permission.
 .B EINVAL
 Target file system doesn't support splicing, none of the descriptors refer
 to a pipe or offset given for non-seekable device.
+.TP
+.B ENOMEM
+Ran out of memory.
 
 .SH HISTORY
 The

diff --git a/tee.2 b/tee.2
index 7d806d482dee9435602770ba3f8ffa7aa8847542..6d4c34818316a46379d135e9a60023f728e92e3f 100644 (file)
--- a/tee.2
+++ b/tee.2
@@ -36,9 +36,12 @@ See
 .BR vmsplice (2)
 
 .PP
+Conceptually,
 .BR tee ()
-doesn't copy any data around, it simply references the input data and
-links it to the output pipe.
+copies the data between the two pipes, in reality no real data copying
+takes place though. Under the covers,
+.BR tee ()
+assigns data in the output by merely grabbing a reference to the input.
 
 .SH RETURN VALUE
 Upon successful completion,
@@ -55,6 +58,54 @@ shall be set to indicate an error.
 and
 .I fd_out
 do not both refer to a pipe.
+.TP
+.B ENOMEM
+Ran out of memory.
+
+.SH EXAMPLE
+The following example implements a basic
+.BR tee (1)
+program using the
+.BR tee (2)
+system call. To keep it simple, it has no real error handling.
+
+.nf
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/splice.h>
+
+int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+
+do {
+       /*
+        * tee stdin to stdout.
+        */
+       int len = tee(STDIN_FILENO, STDOUT_FILENO, INT_MAX, SPLICE_F_NONBLOCK);
+
+       if (len < 0) {
+               if (errno == EAGAIN)
+                       continue;
+               perror("tee");
+               break;
+       } else if (!len)
+               break;
+
+       /*
+        * Consume stdin by splicing it to a file.
+        */
+       while (len) {
+               int slen = splice(STDIN_FILENO, NULL, fd, NULL, len, SPLICE_F_MOVE);
+               if (slen < 0) {
+                       perror("splice");
+                       break;
+               }
+               len -= slen;
+       }
+} while (1);
+
+close(fd);
+.fi
 
 .SH HISTORY
 The

diff --git a/vmsplice.2 b/vmsplice.2
index b0f739a8ffe83a1b0b96bd4682152f756d9cad1d..01bcd14a85275b88f7749623c1da95d5d43c521e 100644 (file)
--- a/vmsplice.2
+++ b/vmsplice.2
@@ -76,6 +76,9 @@ either not valid, or doesn't refer to a pipe.
 not valid, memory not aligned if
 .I SPLICE_F_GIFT
 set.
+.TP
+.B ENOMEM
+Ran out of memory.
 
 .SH NOTES
 .BR vmsplice ()