debian man page for eatmydata

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 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 com-
       mand 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 environ-
       ment 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.

AUTHOR
       The eatmydata wrapper around libeatmydata LD_PRELOAD library was written by Modestas Vainius <modax@debian.org>

								   November 2010						      eatmydata(1)