CCONTROL(1) | CCONTROL(1) |
NAME¶
ccontrol - wrapper to control distcc, ccache and moreSYNOPSIS¶
gcc ... cc ... c++ ... make ... ld ... ccontrol [--section=<section>] <name> ... ccontrol [--section=<section>]DESCRIPTION¶
The ccontrol(1) program takes over the roles of the compiler and linker, and reads a configuration file to decide what to do before invoking them. This is particularly useful for centralized control over commands and options, such as enabling distcc(1) and ccache(1). When ccontrol(1) is invoked under its own name with no arguments, it prints out the settings which apply in this directory (unless --section is specified). Versions are named after the last person to report a bug.OPTIONS¶
Normally ccontrol(1) is invoked as a symboling link to cc, make, etc, so it can identify what is being invoked by examining its own name. It can also be invoked under its own name, in which case ccontrol-specific arguments can be supplied. The first non-option argument will be used to identify the invocation, eg. "ccontrol gcc ...". The following options are supported, when invoked as ccontrol: --section=<section>This is treated as the "current directory" for
the purposes of evaluating the configuration file. As all real directories
must begin with a "/" using an argument which does not, is a good
way of overriding configuration for this particular invocation.
CONFIGURATION FILE¶
ccontrol’s configuration file is $HOME/.ccontrol/config. If this cannot be read (and written), your compilations will all fail. It is normal to have several different configuration files in this directory, and make default a symbolic link.SYNTAX¶
A configuration file consists of sections, led by a "[path]" header and followed by indented "name = value" entries. The first section is usually labelled "[*]" to set up the defaults. At the very least, you must set the "cc", "c++", "make" and "ld" values. ccontrol will read every section which matches the current directory, so you can override values on a per-directory basis. The "[path]" header of each section is a shell-style wildcard (see glob(7)) which indicates the directory or directories it applies to. Usually this will end in a "*" to include all subdirectories. All paths beginning with "~" are relative to the user’s home directory. A path may be specified as a directory, in which case ccontrol will append the program name to the directory. The following settings are available: ccFollowed by = specifies the path of the compiler
to be invoked when ccontrol is invoked as "cc" or "gcc".
ccontrol will fail to compile C programs if this is not set.
c++
Followed by = specifies the path of the compiler
to be invoked when ccontrol is invoked as "c" or "g".
ccontrol will fail to compile C++ programs if this is not set.
ld
Followed by = specifies the path of the linker to
be invoked when ccontrol is invoked as "ld". ccontrol will fail to
link programs if this is not set.
make
Followed by = specifies the path of the binary to
be invoked when ccontrol is invoked as "make". ccontrol will fail to
make if this is not set.
ccache
Followed by = specifies the path of
"ccache", and indicates that ccache is to be used where appropriate.
If followed by disable, or not set, ccache will not be used.
distcc
Followed by = specifies the path of
"distcc", and indicates that distcc is to be used where appropriate.
If followed by disable, or not set, or distcc-hosts is not set, distcc
will not be used.
distcc-hosts
Followed by = specifies the distcc servers to use,
as per the DISTCC_HOSTS environment variable in distcc(1). Followed by
disable disables distcc.
distc++-hosts
The same as distcc-hosts, but only applies to
Ccompilations. If not set, distcc-hosts is used. You can thus disable distcc
for C compilations by setting "distc++-hosts disable".
cpus
Followed by = and a number of CPUs, set to the
number of CPUs you have (the default is "1"). ccontrol uses
this to tune the degree of parallelism.
no-parallel
Followed by = and a space-separated list of
wildcards, suppresses parallel make for any make target matching one of those.
This option is needed because ccontrol(1) usually forces make(1) to perform
all actions in parallel, but this can be confusing when an error occurs, and
breaks poorly-written makefiles. Followed by disable, enables parallel
make for all targets: this is useful to re-enable parallel make in a
subdirectory.
nice
Followed by = and a priority level from -19 to 20,
causes ccontrol to try to set its priority to this value. Default is 10.
include
Followed by = specifies a file to include at the
current point. The effect is exactly as if the contents of the included file
were literally inserted. Can be used at file level to include sections. Can
also be used within sections to include section fragments.
add make
Followed by = specifies an argument to be added to
each invocation of make. This can be specified multiple times to add
multiple arguments. Followed by disable removes any arguments
previously specified.
add env
Followed by = specifies an environment variable to
be set, such as "add env = CCACHE_DIR=/tmp". This can be specified
multiple times to set multiple environment variables. Followed by
disable removes any arguments previously specified.
verbose
By itself, indicates that ccontrol(1) is to spit lots of
crap out to standard error about what it’s doing to your innocent
command line.
lock-file
Specify a particular lock file to use.
EXAMPLES¶
This is the minimal configuration file:[*] cc = /usr/bin/gcc c++ = /usr/bin/g++ ld = /usr/bin/ld make = /usr/bin/make
# Configuration file for when I'm at work. Lots of distcc hosts! include = ~/.ccontrol/global [*] distcc-hosts = snab swarm1 swarm3 swarm4 swarm5 fandango2 mingo distc++-hosts = snab mingo
[*] cc = /usr/bin/gcc-4.0 c++ = /usr/bin/g++-4.0 ld = /usr/bin/ld make = /usr/bin/make # Comment this back in for debugging # verbose distcc = /usr/bin/distcc distcc-hosts = snab swarm1 swarm3 swarm4 swarm5 fandango2 mingo distc++-hosts = snab mingo ccache = /usr/bin/ccache # make check should not generally be run in parallel no-parallel = check # Wesnoth doesn't compile with g++ 4.0 [*wesnoth*] c++ = /usr/bin/g++-3.4 # Stupid third-party modules don't build in parallel. [/usr/src/modules/*] no-parallel = * # Using distcc when testing module-init-tools causes strange effects. [*module-init-tools*/tests/*] distcc disable
BUGS¶
The ~/.ccontrol/config file must be writable: ccontrol(1) needs to get an exclusive write lock on it, which means it needs to open the file for writing. Use include to include read-only files. ccontrol will not immediately notice a change in included files, only in the toplevel file (ccontrol re-reads the config file if it changed while ccontrol was trying to grab a lock). The Linux (⟨ 2.6.15) cpufreq ondemand governor (common on laptops) will not increase CPU speed when using ccontrol(1), because ccontrol re-nices compilations. This can make builds 2-3 times slower. Either use another governor, or tell ondemand to ignore nice values:echo 1 > /sys/devices/system/cpu/cpu0/cpufreq/ondemand/ignore_nice
AUTHOR¶
Written by Rusty Russell < rusty@rustcorp.com.au[1]>LICENSE¶
Copyright © 2005 Rusty Russell. Free use of this software is granted under the terms of the GNU General Public License (GPL).SEE ALSO¶
make(1), cc(1), c++(1), ld(1), distcc(1), ccache(1), glob(7), cpufreq-set(1)AUTHOR¶
Rusty Russell <rusty@rustcorp.com.au>Author.
NOTES¶
- 1.
- rusty@rustcorp.com.au
mailto:rusty@rustcorp.com.au
v0.9 5 January 2006 |