tlbuild: Build iteration

 
 4.1 Build iteration
 ===================
 
 Running the top-level 'configure' script configures the top level and
 the subdirectories 'libs', 'utils', and 'texk'.  Running 'make' at the
 top level first iterates over the TeX-specific libraries, and then runs
 'make' in 'libs', 'utils', and 'texk' to iterate over the generic
 libraries, utility programs, and TeX-specific programs, respectively.
 These iterations consist of two steps:
 
   1. For each library or program module not yet configured, run
      'configure', adding the configure option '--disable-build' if the
      module need not be built, otherwise running 'make all'.
 
   2. For each library or program module that must be built, run 'make'
      for the selected target(s): 'default' or 'all' to (re-)build,
      'check' to run tests, 'install', etc.
 
    Running the top-level 'make' a second time iterates again over all
 the library and program modules, and finds (should find) nothing to be
 done.