NAME

       eatmydata - transparently disable fsync() and other data-to-disk synchronization calls

SYNOPSIS

       eatmydata [--] command [ command arguments ... ]

DESCRIPTION

       eatmydata runs a command in the environment where data-to-disk synchronization calls (like
       fsync(), fdatasync(), sync(), msync() and open() O_SYNC / O_DSYNC flags) have  no  effect.
       LD_PRELOAD library libeatmydata overrides respective C library calls with custom functions
       that don't trigger synchronization but return success nevertheless.

       You may use eatmydata in two ways. In normal mode, just  execute  eatmydata  directly  and
       pass a command-to-be-run and its arguments via command line. In order to use symlink mode,
       create a symlink to /usr/bin/eatmydata with  the  filename  (a.k.a  basename)  of  another
       program  in the PATH and execute eatmydata via that symlink. Then eatmydata will find that
       program in the PATH and run it in the libeatmydata environment repassing all command  line
       options.

OPTIONS

       Please  note that eatmydata does not process any command line options in symlink mode. All
       command line options will be repassed to the underlying executable as-is.

       command
              The command to execute. It may be either a full path or the name of the command  in
              PATH. In case command cannot be found in PATH, eatmydata will fail.

       command arguments
              Arbitrary number of arguments to pass to the command being executed.

       --     Optional command separator for compatibility with similar utilities. Ignored at the
              moment.

EXAMPLES

       Given PATH is /usr/bin and both /usr/bin/aptitude and  /usr/bin/eatmydata  are  installed,
       the following:

           $ ln -s /usr/bin/eatmydata ./aptitude
           $ ./aptitude moo

       is equivalent to:

           $ eatmydata -- aptitude moo

       Therefore,  you  may  use  symlink  mode  to  automatically  run  specific programs in the
       libeatmydata environment whenever you run them from PATH. For example, given standard PATH
       settings, just do:

           # ln -s /usr/bin/eatmydata /usr/local/bin/aptitude

       and enjoy sync-free aptitude system-wide.

CAVEAT

       When  using  eatmydata  with  setarch  (including  alias  such as linux32), or anyway with
       chroots with a different architectures than the host's, make sure to install the  matching
       architecture of libeatmydata1 both in the setarch environment and host's.

       Trying  to  load  libeatmydata  manually  (without  using the wrapper script) and using it
       through a chroot, especially if the eatmydata version differ between outside  and  inside,
       is probably going to fail do the different position of the library on the file system.
       The  safest  way to manually load libeatmydata is by setting the following two environment
       variables (shell syntax):

           LD_LIBRARY_PATH=${LD_LIBRARY_PATH:+"$LD_LIBRARY_PATH:"}/usr/lib/libeatmydata
           LD_PRELOAD=${LD_PRELOAD:+"$LD_PRELOAD "}libeatmydata.so

       These two variables accounts the case of a Debian Jessie host with a Debian Wheezy chroot,
       where the position of the library changed.

                                          November 2014                              eatmydata(1)