NAME

       Bear - Build EAR

SYNOPSIS

       bear [options] [build command]

DESCRIPTION

       Bear is a tool to generate compilation database for clang tooling.

       The  JSON compilation database <http://clang.llvm.org/docs/JSONCompilationDatabase.html> is used in Clang
       project to provide information how a single compilation unit was processed.  When that is available  then
       it is easy to re-run the compilation with different programs.

       Bear  executes the original build command and intercepts the subsequent execution calls.  To achieve that
       Bear uses library preload mechanism provided by the dynamic linker.  There is a library which defines the
       exec  methods  and  used  in  every child processes of the build command.  The executable itself sets the
       environment up to child processes and writes the output file.

OPTIONS

       --version
              Print out Bear version number.

       -v, --verbose
              Enable verbose output from Bear.  A second, third and fourth flags increases verbosity.

       -o file, --cdb file
              Specify output file.  (Default value provided.) The output is not continuously updated, it's  done
              when the build command finished.

       –field-output
              Ask to emit the output field for each entries in the output file.

       --use-cc program
              Hint Bear to classify the given program name as C compiler.

       --use-c++ program
              Hint Bear to classify the given program name as C++ compiler.

       --use-fortran program
              Hint Bear to classify the given program name as Fortran compiler.

       --use-only
              Force to use only the --use-cc and --use-c++ given compilers.

       --include directory
              Only  include  this directories or files to the output.  The flag can be used multiple times.  The
              directory is either absolute or relative to current working directory.  Use  --exclude  to  filter
              entries out from these directory.

       --exclude directory
              Exclude  these  directories  or  files from the output.  The flag can be used multiple times.  The
              directory is either absolute or relative to current working directory.   The  --include  will  not
              enable entries from these directories.

       -a, --append
              Use  previously generated output file and append the new entries to it.  This way you can run Bear
              continuously during work, and it keeps the compilation database up to  date.   File  deletion  and
              addition  are  both  considered.   But  build  process  change (compiler flags change) might cause
              duplicate entries.

       -l path, --libear path
              Specify the preloaded library location.  (Default value provided.)

OUTPUT

       The JSON compilation database definition changed over  time.   The  current  version  of  Bear  generates
       entries where:

       directory
              has absolute path.

       file   has relative path to the directory.

       arguments
              used  instead  of  command to avoid shell escaping problems.  The source file in the compiler call
              match to the file attribute, therefore it is relative path to directory.  Other filesystem related
              references  are  not  modified  (those  still  can  be absolute or relative depending the original
              command).

       Some non compilation related flags are filtered out from the final output.

EXIT STATUS

       Bear exit status is the exit status of the build command.  Except when bear crashes, then it sets to  non
       zero.

ENVIRONMENT

       INTERCEPT_BUILD_TARGET_DIR
              Temporary directory to collect the execution reports at one place.  Directory path is derived from
              TMPDIR, TEMP or TMP environment variable.

       LD_PRELOAD
              Used by the dynamic loader on Linux, FreeBSD and other UNIX OS.   Value  set  by  Bear,  overrides
              previous value for child processes.

       DYLD_INSERT_LIBRARIES
              Used  by  the  dynamic  loader  on  OS  X.   Value set by Bear, overrides previous value for child
              processes.

       DYLD_FORCE_FLAT_NAMESPACE
              Used by the dynamic loader on OS X.  Value  set  by  bear,  overrides  previous  value  for  child
              processes.

FILES

       libear.so or libear.dylib
              The preload library which implements the exec methods.

SEE ALSO

       ld.so(8), exec(3)

BUGS

       Because  Bear  uses  LD_PRELOAD or DYLD_INSERT_LIBRARIES environment variables, it does not append to it,
       but overrides it.  So builds which are using these variables might not work.  (I  don't  know  any  build
       tool which does that, but please let me know if you do.)

       Security  extension/modes  on different operating systems might disable library preloads.  This case Bear
       behaves normally, but the result compilation database will be empty.  (Please make sure it's not the case
       when reporting bugs.) Notable examples for enabled security modes are: SIP on OS X Captain and SELinux on
       Fedora, CentOS, RHEL.

COPYRIGHT

       Copyright (C) 2012-2019 by László Nagy <https://github.com/rizsotto/Bear>

AUTHORS

       László Nagy.