Mas var
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► MAS
mas_var is a program for determining MAS configuration information (especially paths to scripts, data directories, and other configuration files). It was developed to replace the environment-based approach that existed previously, especially for systems using Multicard MAS where more than one fibre card is in use. mas_var queries the mas.cfg configuration file to get the system configuration.
Legacy, single fibre card installations may ignore the availability of mas_var, and simply use MAS_* environmental variables as before without issue. Multicard MAS users will find such an approach difficult.
For a more detailed discussion of environmental variables themselves, see the Environmental variables page.
Contents
Usage
Running mas_var without any options will produce a usage summary. In general, mas_var is invoked as:
mas_var [OPTION]... [PARAMETER]...
The options are:
-c print C shell commands for regularising the environment for
the specified (or default) MCE device. (See below for an
example of use.)
-e ignore any MAS_... environment variables.
-m <file> read MAS configuration from the specified file instead of
the default mas.cfg (the one reported by --config-file)
-n <card> report values for the specified fibre card. Ignored if not
running Multicard MAS.
-Q quiet: don't write warnings.
-q instead of reporting the value on standard output, exit with
non-zero status if the first parameter is false, otherwise
exit with zero status. Only makes sense with a boolean
parameter: all other parameters are implicitly true.
-s print Bourne-compatible shell commands for regularising the
environment for the specified (or default) MCE device.
(See below for an example of use.)
-x when used with -c or -s, only define required environmental
variables, specifically: MAS_MCE_DEV, MAS_PREFIX, and
MAS_VAR, plus modified PATH and PYTHONPATH. If -e is also
specified, the commands output will remove all other MAS
variables from the environment. Ignored if not used
with -c or -s.
The parameters are:
--bigphys boolean; true if the driver supports bigphysarea
--bin-dir the location of the MAS binaries (MAS_BIN in the
environment)
--cflags cc(1) options needed to complile against the MAS libraries
--config-dir the location of the MCE config files (MAS_CONFIG in the
environment)
--config-file the full path of the default MAS configuration file
--data-dir the current data directory (MAS_DATA in theenvironment)
--data-root the root data directory (MAS_DATA_ROOT in the environment)
--etc-dir the directory containing the hardware description files
(MAS_ETC in the environment.)
--experiment-file the full path of the experiment configuration file
--fakemce boolean; true if the driver contains the facemce device
--fibre-card the number of the current fibre card
--group the MAS group
--hardware-file the full path of the hardware configuration file
--idl-dir the MCE script IDL directory (MAS_IDL in the environment)
--int-version an integer SVN revsion number
--jam-dir the location of the JAM firmware files (MAS_JAM_DIR in the
environment)
--libs ld(1) options needed to link to the MAS libraries
--mas-root the base directory for the MCE script tree (MAS_ROOT
in the environment)
--max-fibre-card the maximum number of fibre cards supported
--multicard booelan; true if MAS supports multiple fibre cards
--path[=PATHBASE] a shell PATH variable for MAS. If given, MAS specific
directories will be appended to PATHBASE, otherwise they
will be appended to the current PATH. (See also
--path-base below.)
--path-base the current PATH variable stripped of any directories which
start with the MAS prefix (see --prefix) or the MAS_ROOT
environment variable, if it is defined. The value is
suitable for providing to --path.
--prefix the MAS prefix
--pythonpath[=PATHBASE]
a PYTHONPATH variable for MAS. If given, MAS specific
directories will be appended to PATHBASE, otherwise they
will be appended to the current PYTHONPATH. (See also
--pythonpath-base below.)
--pythonpath-base the current PYTHONPATH variable stripped of any directories
which start with the MAS prefix (see --prefix) or the
MAS_ROOT environment variable, if it is defined. The
value is suitable for providing to --pythonpath.
--python-dir the MCE script python directory (MAS_PYTHON in the
environment)
--script-dir the MCE script directory (MAS_SCRIPT in the environment)
--temp-dir the MAS temporary directory (MAS_TEMP in the environment)
--template-dir the MAS template directory (MAS_TEMPLATE in the environment)
--test-suite the MAS test suite directory (MAS_TEST_SUITE in the
environment)
--user the MAS username
--version the mas_var version
Examples
- Unless -q, -c, or -s is specified, mas_var will print the value of each parameter listed, one per line, in the order given on the command line:
user@ubuntu:~$ mas_var --version --user --prefix --mas-root --data-dir MAS/trunk/739 mce /usr/mce /usr/mce/mce_script /data/cryo/current_data
- If -q is specified, mas_var prints nothing but exits with non-zero status if the first parameter is false. This only makes sense with boolean parameters (--bigphys or --fakemce):
user@ubuntu:~$ mas_var --fakemce --bigphys False True user@ubuntu:-$ if mas_var -q --bigphys; then echo "Bigphys enabled"; else echo "Bigphys disabled"; fi Bigphys enabled user@ubuntu:-$ if mas_var -q --fakemce; then echo "FakeMCE present"; else echo "FakeMCE absent"; fi FakeMCE absent
- If -m is used to specify a different mas.cfg file, results will change to reflect the different MAS configuration:
user@ubuntu:~$ mas_var --etc-dir /etc/mce user@ubuntu:~$ grep etcdir ~/mas.cfg etcdir = "/usr/local/etc/mce"; user@ubuntu:~$ mas_var -m ~/mas.cfg --etc-dir /usr/local/etc/mce
- Perhaps surprisingly, the exception to this is the --config-file parameter (which reports the location of mas.cfg). It ignores -m completely and always reports the default mas.cfg location:
user@ubuntu:~$ mas_var --config-file /etc/mce/mas.cfg user@ubuntu:~$ mas_var -m ~/mas.cfg --config-file /etc/mce/mas.cfg
- (this is because a default mas.cfg path is hard-coded into the MAS library at build time to resolve the chicken-and-egg problem of having to read mas.cfg to determine the location of mas.cfg). See also the MAS_MAS_CFG environmental variable.
- If -s is given, Bourne-compatible shell commands are printed for "regularising" the environment:
user@ubuntu:~$ mas_var -s export MAS_VAR="/usr/mce/bin/mas_var"; export MAS_MCE_DEV="0"; export MAS_PREFIX="/usr/mce"; export MAS_ROOT="/usr/mce/mce_script"; export MAS_BIN="/usr/mce/bin"; export MAS_CONFIG="/usr/mce/config"; export MAS_JAM_DIR="/usr/mce/firmware"; export MAS_TEMP="/tmp"; export MAS_DATA_ROOT="/data/cryo"; export MAS_DATA="/data/cryo/current_data"; export MAS_IDL="/usr/mce/mce_script/idl_pro"; export MAS_PYTHON="/usr/mce/mce_script/python"; export MAS_SCRIPT="/usr/mce/mce_script/script"; export MAS_TEMPLATE="/usr/mce/mce_script/template"; export MAS_TEST_SUITE="/usr/mce/mce_script/test_suite"; export PATH="/usr/local/bin:/usr/bin:/bin:/usr/mce/bin:/usr/mce/mce_script/script:/usr/mce/mce_script/test_suite"; export PYTHONPATH="/usr/mce/mce_script/python:/usr/mce/python";
- Similarly, in the C Shell, -c can be used. If MAS_... environmental variables are already defined, they will be left unchanged, simply repeated in the output, unless -e is also specified, telling mas_var to ignore the current environment. In Multicard MAS, if -x is specified along with -s or -c, only a minimal set of environmental variables will be set. This can be advantageous in certain situations; see the discussion in Multicard MAS for details.
- Other points of interest:
- This output includes a definition of MAS_PREFIX in it's output, even though neither MAS nor the MCE scripts ever make use of it
- This output does not include a definition for MAS_MAS_CFG, even though mas_var will consult it, if it is defined.
- These options (-s and -c) are most useful when mas_var is run inside back-ticks (`) and the output sent through eval to update the currently executing shell's environment; see below.
mas_var as a replacement for the MAS environment variables
The scripts and tuning programs no longer require that the $MAS_* environment variables be defined. Instead, they will run mas_var to determine the necessary paths, based on information in mas.cfg. If $MAS_VAR is defined, that is assumed to be the path to mas_var, otherwise /usr/mce/bin/mas_var is used.
The standard MAS environment variables can be set using mas_var
When running from the command line it is sometimes convenient to have the $MAS_* variables defined, and to update $PATH and $PYTHONPATH for the MAS software. To achieve this in bash, run:
eval `mas_var -e -s`
(note the back ticks). This line can be put in a user's .bashrc, to be run at login as a replacement for the older "source $MAS_ROOT/template/mas_env.bash".
Environment variables override the settings in mas.cfg
Note that environment variables can be used to override the settings in mas.cfg -- this can be useful in cases where one would like to temporarily switch parts of an installation or the data directory:
user@ubuntu:~$ mas_var --script-dir /usr/mce/mce_script/script user@ubuntu:~$ export MAS_SCRIPT=/home/user/code/mce_script/script user@ubuntu:~$ mas_var --script-dir /home/user/code/mce_script/script
Because the MCE scripts obtain paths through mas_var, the environmental override with be propagated to them as well.
The -e option disables this behaviour, making mas_var ignore the environment:
user@ubuntu:~$ export MAS_SCRIPT=/home/user/code/mce_script/script user@ubuntu:~$ mas_var --script-dir /home/user/code/mce_script/script user@ubuntu:~$ mas_var -e --script-dir /usr/mce/mce_script/script
