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Manual: eatmydata

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eatmydata(1)					   General Commands Manual					eatmydata(1)

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  respecā€
       tive 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  fileā€
       name (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	canā€
	      not 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  archiā€
       tectures	 than  the host's, make sure to install the matching architecture of libeatmydata1 both in the setarch enviā€
       ronment 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)
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