SCons provides a number of ways that allow the writer of the SConscript files to give users a great deal of control over how to run the builds.
Users may find themselves supplying the same command-line options every time they run SCons. For example, a user might find that it saves time to specify a value of -j 2 to run the builds in parallel. To avoid having to type -j 2 by hand every time, you can set the external environment variable SCONSFLAGS to a string containing command-line options that you want SCons to use.
If, for example, and you're using a POSIX shell that's compatible with the Bourne shell, and you always want SCons to use the -Q option, you can set the SCONSFLAGS environment as follows:
% scons scons: Reading SConscript files ... scons: done reading SConscript files. scons: Building targets ... ... [build output] ... scons: done building targets. % export SCONSFLAGS="-Q" % scons ... [build output] ...
Users of csh-style shells on POSIX systems can set the SCONSFLAGS environment as follows:
$ setenv SCONSFLAGS "-Q"
Windows users may typically want to set this SCONSFLAGS in the appropriate tab of the System Properties window.