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Ed Schouten c0086bf202 Serialize write() calls on TTYs.
Just like the old TTY layer, the current MPSAFE TTY layer does not make
any attempt to serialize calls of write(). Data is copied into the
kernel in 256 (TTY_STACKBUF) byte chunks. If a write() call occurs at
the same time, the data may interleave. This is especially likely when
the TTY starts blocking, because the output queue reaches the high
watermark.

I've implemented this by adding a new flag, TTY_BUSY_OUT, which is used
to mark a TTY as having a thread stuck in write(). Because I don't want
non-blocking processes to be possibly blocked by a sleeping thread, I'm
still allowing it to bypass the protection. According to this message,
the Linux kernel returns EAGAIN in such cases, but I think that's a
little too restrictive:

	http://kerneltrap.org/index.php?q=mailarchive/linux-kernel/2007/5/2/85418/thread

PR:		kern/118287
2009-02-11 16:28:49 +00:00
bin Before this fix, pax would stop the restore sequence for 2009-02-01 06:15:46 +00:00
cddl Correct the sense of the "use32" terenary operator so that it uses 2009-01-16 22:16:54 +00:00
contrib - Fix an issue where file attributes were not installed correctly during a Touch 2009-02-09 20:13:55 +00:00
crypto Prevent cross-site forgery attacks on lukemftpd(8) due to splitting 2009-01-07 20:17:55 +00:00
etc Reword informational message by rc.d/defaultroute. 2009-02-11 09:18:09 +00:00
games netcat is "now" in base, so point people at nc(1) instead of the port. 2009-01-12 19:17:43 +00:00
gnu For files not named on the command line, only the basename is compared 2009-01-30 00:22:08 +00:00
include Also un-split _PATH_STDPATH for grepability. 2009-02-01 00:50:46 +00:00
kerberos5 Add strndup(3) prototype to string.h. 2008-12-08 21:04:24 +00:00
lib - Sanitize disk parameters retrieved from GEOM, as they are not guaranteed to 2009-02-09 21:34:06 +00:00
libexec o Fix typo: indentical -> identical. 2009-01-30 09:42:25 +00:00
release Turn off the parallel make options accidentally turned on by the previous 2009-02-10 15:11:26 +00:00
rescue Take a moment to tidy some white space while I'm here. No functional 2008-09-13 19:56:37 +00:00
sbin Prefer the start and end attributes over the offset and size 2009-02-08 20:19:19 +00:00
secure Enable getaudit_addr(2) for sshd again. This will un-break the subject 2008-11-30 15:35:24 +00:00
share Document loader tunable hw.re.msi_disable. 2009-02-09 05:09:52 +00:00
sys Serialize write() calls on TTYs. 2009-02-11 16:28:49 +00:00
tools Add a regresion test to determine whether or not a file descriptor is 2009-02-11 13:44:27 +00:00
usr.bin o Print an octal representation of suid, sgid and sticky bits with -x flag. 2009-02-11 10:50:26 +00:00
usr.sbin Serialize write() calls on TTYs. 2009-02-11 16:28:49 +00:00
COPYRIGHT Bump the odometer of the years. A little early this year for 7.1R. 2008-12-30 04:46:25 +00:00
LOCKS Update LOCKS syntax. 2008-06-05 19:47:58 +00:00
MAINTAINERS Update description text 2008-06-06 21:32:01 +00:00
Makefile Permit digits at the beginning and end of kernel config file names for 2008-12-27 15:07:51 +00:00
Makefile.inc1 Implement an idea from Sam Leffler: 2009-01-23 18:23:16 +00:00
ObsoleteFiles.inc Reflect adding_user.8 -> adding_user.7 rename 2009-02-03 20:46:05 +00:00
README Simply running ``make world'' will bomb unless you dig up the 2006-06-07 03:33:48 +00:00
UPDATING Add a note to document that ichsmb(4) now uses left-justified SMBus slave 2009-02-06 15:03:14 +00:00

This is the top level of the FreeBSD source directory.  This file
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The sample kernel configuration files reside in the sys/<arch>/conf
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Source Roadmap:
---------------
bin		System/user commands.

contrib		Packages contributed by 3rd parties.

crypto		Cryptography stuff (see crypto/README).

etc		Template files for /etc.

games		Amusements.

gnu		Various commands and libraries under the GNU Public License.
		Please see gnu/COPYING* for more information.

include		System include files.

kerberos5	Kerberos5 (Heimdal) package.

lib		System libraries.

libexec		System daemons.

release		Release building Makefile & associated tools.

rescue		Build system for statically linked /rescue utilities.

sbin		System commands.

secure		Cryptographic libraries and commands.

share		Shared resources.

sys		Kernel sources.

tools		Utilities for regression testing and miscellaneous tasks.

usr.bin		User commands.

usr.sbin	System administration commands.


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  http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html