distcc.1

distcc编译器的源代码.好像是readhat公司开发的.

server.  This is normally only needed if for some reason you can't
install distccd into a directory on the default PATH for SSH
connections.  Use this if you get errors like "distccd: command not
found" in SSH mode.     
.TP
.B /LIMIT
A decimal limit can be added to any host specification to restrict the
number of jobs that this client will send to the machine.  The limit
defaults to four per host (two for localhost), but may be further
restricted by the server.  You should only need to increase this for
servers with more than two processors.
.TP
.B ,lzo
Enables LZO compression for this TCP or SSH host.
.PP
Here is an example demonstrating some possibilities:
.PP
.RS
.nf
.B localhost/2 @bigman/16:/opt/bin/distccd oldmachine:4200/1
.B  # cartman is down
.B distant/3,lzo
.fi
.RE
.PP
Comments are allowed in host specifications.  Comments start with a
hash/pound sign (\fB#\fP) and run to the end of the line.
.PP
If a host in the list is not reachable distcc will emit a warning and
ignore that host for about one minute.
.SH "COMPRESSION"
The 
.B lzo 
host option specifies that LZO compression should be used for data
transfer, including preprocessed source, object code and error
messages.  Compression is usually economical on networks slower than
100Mbps, but results may vary depending on the network, processors and
source tree.
.PP 
Enabling compression makes the distcc client and server use more CPU
time, but less network traffic.  The compression ratio is typically
4:1 for source and 2:1 for object code.
.PP
Using compression requires both client and server to use at least
release 2.9 of distcc.  No server configuration is required: the
server always responds with compressed replies to compressed requests.
.SH "SEARCH PATHS"
.PP
If the compiler name is an absolute path, it is passed verbatim to the
server and the compiler is run from that directory.  For example:
.PP
.RS
.B distcc /usr/local/bin/gcc-3.1415 -c hello.c
.RE
.PP
If the compiler name is not absolute, or not fully qualified,
distccd's PATH is searched.  When distcc is run from a masquerade
directory, only the base name of the compiler is used.  The client's
PATH is used only to run the preprocessor and has no effect on the
server's path.
.SH "TIMEOUTS"
.PP
Both the distcc client and server impose timeouts on transfer of data
across the network.  This is intended to detect hosts which are down
or unreachable, and to prevent compiles hanging indefinitely if a
server is disconnected while in use.  If a client-side timeout
expires, the job will be re-run locally.
.PP
The timeouts are not configurable at present.
.SH "DIAGNOSTICS"
Error messages or warnings from local or remote compilers are passed
through to diagnostic output on the client.
.PP
distcc can supply extensive debugging information when the verbose
option is used.  This is controlled by the 
.B DISTCC_VERBOSE
environment variable on the client, and the
.B --verbose
option on the server.  For troubleshooting, examine both the client
and server error messages.
.SH "EXIT CODES"
The exit code of distcc is normally that of the compiler:
zero for successful compilation and non-zero otherwise.
.PP
distcc distinguishes between "genuine" errors such as a syntax error
in the source, and "accidental" errors such as a networking problem
connecting to a volunteer.  In the case of accidental errors, distcc
will retry the compilation locally unless the DISTCC_FALLBACK option
has been disabled.
.PP
If the compiler exits with a signal, distcc returns an exit code of
128 plus the signal number.
.PP
distcc internal errors cause an exit code between 100 and 127.  In
particular
.TP
100
General distcc failure.
.TP 
105
Out of memory.
.TP 
110
Compiler not found.
.TP
111
Recursive call to distcc.
.TP 
116
No hosts defined and fallbacks disabled.
.PP
(Others are listed in exitcode.h.)
.SH "FILES"
If $DISTCC_HOSTS is not set, distcc reads a host list from either 
.B $DISTCC_DIR/hosts
or a system-wide configuration file set at compile time.  The file
locations are shown in the output from
.B distcc --help
.PP
distcc creates a number of temporary and lock files underneath the
temporary directory.
.SH "ENVIRONMENT VARIABLES"
distcc's behaviour is controlled by a number of environment variables.
For most cases nothing need be set if the host list is stored in a
file.
.TP
.B "DISTCC_HOSTS"
Space-separated list of volunteer host specifications.
.TP
.B "DISTCC_VERBOSE"
If set to 1, distcc produces explanatory messages on the standard
error stream or in the log file.  This can be helpful in debugging
problems.  Bug reports should include verbose output.
.TP
.B "DISTCC_LOG"
Log file to receive messages from distcc itself, rather
than stderr.
.TP
.B "DISTCC_FALLBACK"
By default distcc will compile locally if it fails to distribute a job
to the intended machine, or if no host list can be found.  If this
variable is set to 0 then fallbacks are disabled and those
compilations will simply fail.  Note that this does not affect jobs
which must always be local such as linking.
.TP
.B "DISTCC_SAVE_TEMPS"
If set to 1, temporary files are not deleted after use.  Good for
debugging, or if your disks are too empty.
.TP
.B "DISTCC_TCP_CORK"
If set to 0, disable use of "TCP corks", even if they're present on
this system.  Using corks normally helps pack requests into fewer
packets and aids performance.  This should normally be left enabled.
.TP
.B DISTCC_SSH
Specifies the command used for opening SSH connections.  Defaults to
"ssh" but may be set to a different connection command such as "lsh"
or "tsocks-ssh" that accepts a similar command line.  The command is
not split into words and is not executed through the shell. 
.TP
.B "DISTCC_DIR"
Per-user configuration directory to store lock files and state files.
By default 
.B ~/.distcc/ 
is used.
.TP
.B "TMPDIR"
Directory for temporary files such as preprocessor output.  By default
/tmp/ is used.
.TP
.B "UNCACHED_ERR_FD"
If set and if DISTCC_LOG is not set, distcc errors are written to the
file descriptor identified by this variable.  This variable is
intended mainly for automatic use by ccache, which sets it to avoid
caching transient errors such as network problems.
.SH "CROSS COMPILING"
Cross compilation means building programs to run on a
machine with a different processor, architecture, or
operating system to where they were compiled.  distcc
supports cross compilation, including teams of
mixed-architecture machines, although some changes to the
compilation commands may be required.
.PP
The compilation command passed to distcc must be one that
will execute properly on every volunteer machine to produce
an object file of the appropriate type.  If the machines
have different processors, then simply using 
.B distcc cc
will probably not work, because that will normally invoke the
volunteer's native compiler.
.PP
Machines with the same CPU but different operating systems may not
necessarily generate compatible .o files.
.PP
Several different gcc configurations can be installed
side-by-side on any machine.  If you build gcc from source,
you should use the 
.B --program-suffix configuration
options to cause it to be installed with a name that encodes
the gcc version and the target platform.
.PP
The recommended convention for the gcc name is
.I TARGET-gcc-VERSION
such as
.B i686-linux-gcc-3.2
\&.  GCC 3.3 will install itself
under this name, in addition to 
.I TARGET-gcc
and, if it's native, 
.I gcc-VERSION 
and 
.I gcc
\&. 
.PP
The compiler must be installed under the same name on the
client and on every volunteer machine.
.SH "BUGS"
If you think you have found a  distcc bug, please see the file
.I reporting-bugs.txt
in the documentation directory for information on how to report it.
.PP
Some makefiles have missing or extra dependencies that cause incorrect
or slow parallel builds.  Recursive make is inefficient and can leave
processors unnecessarily idle for long periods.  (See
.I Recursive Make Considered Harmful
by Peter Miller.)  Makefile bugs are the most common cause of trees
failing to build under distcc.  Alternatives to Make such as
.I SCons
can give much faster builds for some projects.
.PP
Using different versions of gcc can cause confusing build problems
because the header files and binary interfaces have changed over time,
and some distributors have included incompatible patches without
changing the version number.  distcc does not protect against using
incompatible versions.  Compiler errors about link problems or
declarations in system header files are usually due to mismatched or
incorrectly installed compilers.
.PP
Due to limitations in gcc, gdb may not be able to automatically find
the source files for programs built using distcc in some
circumstances.  The gdb 
.B directory
command can be used.  This should be fixed in gcc 3.4.
.PP
gcc's 
.B -MD 
option can produce output in the wrong directory if the source and
object files are in different directories and the 
.B -MF 
option is not used.  There is no perfect solution because of
incompatible changes between gcc versions.  Explicitly specifying the
dependency output file with 
.B -MF
will fix the problem.
.PP
TCP mode connections should only be used on trusted networks.
.PP
Including slow machines in the list of volunteer hosts can slow the
build down.
.PP
When distcc or ccache is used on NFS, the filesystem must be exported
with the
.B no_subtree_check 
option to allow reliable renames between directories.
.PP
The compiler can be invoked with a command line
.B gcc hello.c
to both compile and link.  distcc doesn't split this into separate
parts, but rather runs the whole thing locally.
.PP
Other known bugs may be documented on 
.I http://distcc.samba.org/
.SH "AUTHOR"
distcc was written by Martin Pool <[e-mail]>, with the
co-operation of many scholars including Wayne Davison, Frerich Raabe,
Dimitri Papadopoulos and others noted in the NEWS file.  Please report
bugs to <[e-mail]>.
.SH "LICENCE"
You are free to use distcc.  distcc (including this manual) may be
copied, modified or distributed only under the terms of the GNU
General Public Licence version 2 or later.  distcc comes with
absolutely no warrany.  A copy of the GPL is included in the file
COPYING.
.SH "SEE ALSO"
distccd(1), ccache(1), gcc(1), make(1)
.I http://distcc.samba.org/
.I http://ccache.samba.org/