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NAME

       lcov - a graphical GCOV front-end

SYNOPSIS

       lcov -c|--capture
            [-d|--directory directory] [-k|--kernel-directory directory]
            [-o|--output-file tracefile] [-t|--test-name testname]
            [-b|--base-directory directory] [-i|--initial] [--gcov-tool tool]
            [--checksum] [--no-checksum] [--no-recursion] [-f|--follow]
            [--compat-libtool] [--no-compat-libtool] [--ignore-errors errors]
            [--to-package package] [--from-package package] [-q|--quiet]
            [--no-markers]

       lcov -z|--zerocounters
            [-d|--directory directory] [--no-recursion] [-f|--follow]
            [-q|--quiet]

       lcov -l|--list tracefile
            [-q|--quiet]

       lcov -a|--add-tracefile tracefile
            [-o|--output-file tracefile] [--checksum] [--no-checksum]
            [-q|--quiet]

       lcov -e|--extract tracefile pattern
            [-o|--output-file tracefile] [--checksum] [--no-checksum]
            [-q|--quiet]

       lcov -r|--remove tracefile pattern
            [-o|--output-file tracefile] [--checksum] [--no-checksum]
            [-q|--quiet]

       lcov --diff tracefile diff
            [-o|--output-file tracefile] [--checksum] [--no-checksum]
            [--convert-filenames] [--strip depth] [--path path] [-q|--quiet]

       lcov [-h|--help] [-v|--version]

DESCRIPTION

       lcov  is a graphical front-end for GCC’s coverage testing tool gcov. It
       collects line, function and branch coverage data  for  multiple  source
       files  and creates HTML pages containing the source code annotated with
       coverage information.  It also adds overview pages for easy  navigation
       within the file structure.

       Use  lcov  to  collect  coverage data and genhtml to create HTML pages.
       Coverage data can either be collected from the currently running  Linux
       kernel  or  from  a  user  space  application.  To do this, you have to
       complete the following preparation steps:

       For Linux kernel coverage:
              Follow   the   setup   instructions    for    the    gcov-kernel
              infrastructure: http://ltp.sourceforge.net/coverage/gcov.php

       For user space application coverage:
              Compile   the   application   with   GCC   using   the   options
              "-fprofile-arcs" and "-ftest-coverage".

       Please note that this man page refers to the output format of  lcov  as
       ".info  file" or "tracefile" and that the output of GCOV is called ".da
       file".

OPTIONS

       -a tracefile
       --add-tracefile tracefile
              Add contents of tracefile.

              Specify several tracefiles using the -a switch  to  combine  the
              coverage  data  contained  in these files by adding up execution
              counts for matching test and filename combinations.

              The result of the add operation will be written to stdout or the
              tracefile specified with -o.

              Only  one  of -z, -c, -a, -e, -r, -l and --diff may be specified
              at a time.

       -b directory
       --base-directory directory
              Use directory as base directory for relative paths.

              Use  this  option  to  specify   the   base   directory   of   a
              build-environment when lcov produces error messages like:

                     ERROR:      could      not      read      source     file
                     /home/user/project/subdir1/subdir2/subdir1/subdir2/file.c

              In this example, use /home/user/project as base directory.

              This  option  is required when using lcov on projects built with
              libtool or similar build environments  that  work  with  a  base
              directory,   i.e.   environments,   where  the  current  working
              directory when invoking the compiler is not the  same  directory
              in which the source code file is located.

              Note  that  this  option  will  not  work  in environments where
              multiple base directories are used. In that case repeat the lcov
              call  for  each  base  directory while using the --ignore-errors
              option to prevent lcov from exiting when the first  source  code
              file  could  not be found. This way you can get partial coverage
              information for each base directory which can then  be  combined
              using the -a option.

       -c
       --capture
              Capture coverage data.

              By  default  captures  the  current  kernel execution counts and
              writes the resulting coverage data to the standard  output.  Use
              the  --directory  option  to  capture  counts  for  a user space
              program.

              The result of the capture operation will be written to stdout or
              the tracefile specified with -o.

              Only  one  of -z, -c, -a, -e, -r, -l and --diff may be specified
              at a time.

       --checksum
       --no-checksum
              Specify  whether  to  generate  checksum   data   when   writing
              tracefiles.

              Use --checksum to enable checksum generation or --no-checksum to
              disable it. Checksum generation is disabled by default.

              When  checksum  generation  is  enabled,  a  checksum  will   be
              generated  for  each  source code line and stored along with the
              coverage data. This checksum will be used to prevent attempts to
              combine coverage data from different source code versions.

              If  you  don’t work with different source code versions, disable
              this option to speed up coverage data processing and  to  reduce
              the size of tracefiles.

       --compat-libtool
       --no-compat-libtool
              Specify whether to enable libtool compatibility mode.

              Use  --compat-libtool  to  enable  libtool compatibility mode or
              --no-compat-libtool to disable  it.  The  libtool  compatibility
              mode is enabled by default.

              When  libtool  compatibility  mode  is enabled, lcov will assume
              that the source code  relating  to  a  .da  file  located  in  a
              directory named ".libs" can be found in its parent directory.

              If  you have directories named ".libs" in your build environment
              but don’t use libtool, disable this option to  prevent  problems
              when capturing coverage data.

       --convert-filenames
              Convert filenames when applying diff.

              Use this option together with --diff to rename the file names of
              processed data sets according to the data provided by the  diff.

       --diff tracefile difffile
              Convert  coverage  data in tracefile using source code diff file
              difffile.

              Use this  option  if  you  want  to  merge  coverage  data  from
              different  source  code  levels of a program, e.g. when you have
              data taken from an older version and want  to  combine  it  with
              data  from  a more current version.  lcov will try to map source
              code lines between those versions and adjust the  coverage  data
              respectively.   difffile  needs to be in unified format, i.e. it
              has to be created using the "-u" option of the diff tool.

              Note that lines which are not present in the  old  version  will
              not  be  counted as instrumented, therefore tracefiles resulting
              from this operation should not be interpreted  individually  but
              together  with  other  tracefiles  taken from the newer version.
              Also keep in mind that converted coverage data  should  only  be
              used  for  overview  purposes as the process itself introduces a
              loss of accuracy.

              The result of the diff operation will be written  to  stdout  or
              the tracefile specified with -o.

              Only  one  of -z, -c, -a, -e, -r, -l and --diff may be specified
              at a time.

       -d directory
       --directory directory
              Use .da files in directory instead of kernel.

              If you want to work on coverage data for a user  space  program,
              use  this  option  to specify the location where the program was
              compiled (that’s where the counter files ending with .da will be
              stored).

              Note that you may specify this option more than once.

       -e tracefile pattern
       --extract tracefile pattern
              Extract data from tracefile.

              Use  this switch if you want to extract coverage data for only a
              particular set of files from  a  tracefile.  Additional  command
              line  parameters  will be interpreted as shell wildcard patterns
              (note that they may need to be escaped  accordingly  to  prevent
              the  shell  from  expanding  them  first).   Every file entry in
              tracefile which matches at least one of those patterns  will  be
              extracted.

              The result of the extract operation will be written to stdout or
              the tracefile specified with -o.

              Only one of -z, -c, -a, -e, -r, -l and --diff may  be  specified
              at a time.

       -f
       --follow
              Follow links when searching for .da files.

       --from-package package
              Use .da files in package instead of kernel or directory.

              Use this option if you have separate machines for build and test
              and want to  perform  the  .info  file  creation  on  the  build
              machine. See --to-package for more information.

       --gcov-tool tool
              Specify the location of the gcov tool.

       -h
       --help
              Print a short help text, then exit.

       --ignore-errors errors
              Specify a list of errors after which to continue processing.

              Use  this  option  to  specify  a list of one or more classes of
              errors after which lcov should continue  processing  instead  of
              aborting.

              errors can be a comma-separated list of the following keywords:

              gcov: the gcov tool returned with a non-zero return code.

              source:  the source code file for a data set could not be found.

       -i
       --initial
              Capture initial zero coverage data.

              Run lcov with -c and this option on the  directories  containing
              .bb,  .bbg  or  .gcno  files  before  running any test case. The
              result is a "baseline" coverage data  file  that  contains  zero
              coverage  for  every  instrumented line.  Combine this data file
              (using lcov -a) with coverage data files captured after  a  test
              run  to  ensure  that  the  percentage of total lines covered is
              correct even when not all source code files were  loaded  during
              the test.

              Recommended procedure when capturing data for a test case:

              1. create baseline coverage data file
                     # lcov -c -i -d appdir -o app_base.info

              2. perform test
                     # appdir/test

              3. create test coverage data file
                     # lcov -c -d appdir -o app_test.info

              4. combine baseline and test coverage data
                     #    lcov    -a   app_base.info   -a   app_test.info   -o
                     app_total.info

       -k subdirectory
       --kernel-directory subdirectory
              Capture kernel coverage data only from subdirectory.

              Use this option if you don’t want to get coverage data  for  all
              of the kernel, but only for specific subdirectories. This option
              may be specified more than once.

              Note that you may need to specify the full path  to  the  kernel
              subdirectory  depending  on  the  version  of  the  kernel  gcov
              support.

       -l tracefile
       --list tracefile
              List the contents of the tracefile.

              Only one of  -z, -c, -a, -e, -r, -l and --diff may be  specified
              at a time.

       --no-markers
              Use  this option if you want to get coverage data without regard
              to exclusion markers in the source code file.  See  geninfo  (1)
              for details on exclusion markers.

       --no-recursion
              Use  this  option  if  you  want  to  get  coverage data for the
              specified directory only without processing subdirectories.

       -o tracefile
       --output-file tracefile
              Write data to tracefile instead of stdout.

              Specify "-" as a filename to use the standard output.

              By convention, lcov-generated coverage  data  files  are  called
              "tracefiles" and should have the filename extension ".info".

       --path path
              Strip path from filenames when applying diff.

              Use  this  option together with --diff to tell lcov to disregard
              the specified  initial  path  component  when  matching  between
              tracefile and diff filenames.

       -q
       --quiet
              Do not print progress messages.

              This  option  is implied when no output filename is specified to
              prevent progress messages to mess with coverage  data  which  is
              also printed to the standard output.

       -r tracefile pattern
       --remove tracefile pattern
              Remove data from tracefile.

              Use  this  switch  if  you  want  to  remove coverage data for a
              particular set of files from  a  tracefile.  Additional  command
              line  parameters  will be interpreted as shell wildcard patterns
              (note that they may need to be escaped  accordingly  to  prevent
              the  shell  from  expanding  them  first).   Every file entry in
              tracefile which matches at least one of those patterns  will  be
              removed.

              The  result of the remove operation will be written to stdout or
              the tracefile specified with -o.

              Only one of -z, -c, -a, -e, -r, -l and --diff may  be  specified
              at a time.

       --strip depth
              Strip path components when applying diff.

              Use  this  option together with --diff to tell lcov to disregard
              the  specified  number  of  initial  directories  when  matching
              tracefile and diff filenames.

       -t testname
       --test-name testname
              Specify test name to be stored in the tracefile.

              This name identifies a coverage data set when more than one data
              set is merged into a combined tracefile (see option -a).

              Valid test names can consist of letters, decimal digits and  the
              underscore character ("_").

       --to-package package
              Store .da files for later processing.

              Use this option if you have separate machines for build and test
              and want to  perform  the  .info  file  creation  on  the  build
              machine. To do this, follow these steps:

              On the test machine:
                     - run the test
                     - run lcov -c [-d directory] --to-package file
                     - copy file to the build machine

              On the build machine:
                     - run lcov -c --from-package file [-o and other options]

              This  works  for  both kernel and user space coverage data. Note
              that you might have to specify the path to the  build  directory
              using  -b  with either --to-package or --from-package. Note also
              that the package data must be converted to a .info  file  before
              recompiling the program or it will become invalid.

       -v
       --version
              Print version number, then exit.

       -z
       --zerocounters
              Reset all execution counts to zero.

              By  default  tries  to  reset  kernel  execution counts. Use the
              --directory option  to  reset  all  counters  of  a  user  space
              program.

              Only  one  of -z, -c, -a, -e, -r, -l and --diff may be specified
              at a time.

FILES

       /etc/lcovrc
              The system-wide configuration file.

       ~/.lcovrc
              The per-user configuration file.

AUTHOR

       Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com>

SEE ALSO

       lcovrc(5), genhtml(1), geninfo(1), genpng(1), gendesc(1), gcov(1)