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XARGS(1)		FreeBSD	General	Commands Manual		      XARGS(1)

     xargs -- construct	argument list(s) and execute utility

     xargs [-0]	[-J replstr] [-n number	[-x]] [-s size]	[-t]
	   [utility [argument ...]]

     The xargs utility reads space, tab, newline and end-of-file delimited
     arguments from the	standard input and executes the	specified utility with
     them as arguments.

     The utility and any arguments specified on	the command line are given to
     the utility upon each invocation, followed	by some	number of the argu-
     ments read	from standard input.  The utility is repeatedly	executed until
     standard input is exhausted.

     Spaces, tabs and newlines may be embedded in arguments using single
     (`` ' '') or double (``"'') quotes	or backslashes (``\'').	 Single	quotes
     escape all	non-single quote characters, excluding newlines, up to the
     matching single quote.  Double quotes escape all non-double quote charac-
     ters, excluding newlines, up to the matching double quote.	 Any single
     character,	including newlines, may	be escaped by a	backslash.

     The options are as	follows:

     -0	     Change xargs to expect NUL	(``\0'') characters as separators,
	     instead of	spaces and newlines.  This is expected to be used in
	     concert with the -print0 function in find(1).

     -J	replstr
	     If	this option is specified, xargs	will use the data read from
	     standard input to replace the first occurrence of replstr instead
	     of	appending that data after all other arguments.	This option
	     will not effect how many arguments	will be	read from input	(-n),
	     or	the size of the	command(s) xargs will generate (-s).  The
	     option just moves where those arguments will be placed in the
	     command(s)	that are executed.  The	replstr	must show up as	a dis-
	     tinct argument to xargs.  It will not be recognized if, for
	     instance, it is in	the middle of a	quoted string.	Furthermore,
	     only the first occurrence of the replstr will be replaced.	 For
	     example, the following command will copy the list of files	and
	     directories which start with an uppercase letter in the current
	     directory to destdir:

		   /bin/ls -1d [A-Z]* |	xargs -J [] cp -rp [] destdir

     -n	number
	     Set the maximum number of arguments taken from standard input for
	     each invocation of	the utility.  An invocation of utility will
	     use less than number standard input arguments if the number of
	     bytes accumulated (see the	-s option) exceeds the specified size
	     or	there are fewer	than number arguments remaining	for the	last
	     invocation	of utility.  The current default value for number is

     -s	size
	     Set the maximum number of bytes for the command line length pro-
	     vided to utility.	The sum	of the length of the utility name and
	     the arguments passed to utility (including	NULL terminators) will
	     be	less than or equal to this number.  The	current	default	value
	     for size is ARG_MAX - 2048.

     -t	     Echo the command to be executed to	standard error immediately
	     before it is executed.

     -x	     Force xargs to terminate immediately if a command line containing
	     number arguments will not fit in the specified (or	default) com-
	     mand line length.

     If	no utility is specified, echo(1) is used.

     Undefined behavior	may occur if utility reads from	the standard input.

     The xargs utility exits immediately (without processing any further
     input) if a command line cannot be	assembled, utility cannot be invoked,
     an	invocation of the utility is terminated	by a signal or an invocation
     of	the utility exits with a value of 255.

     The xargs utility exits with a value of 0 if no error occurs.  If utility
     cannot be invoked,	xargs exits with a value of 127.  If any other error
     occurs, xargs exits with a	value of 1.

     echo(1), find(1)

     The xargs utility is expected to be IEEE Std 1003.2 (``POSIX.2'') compli-
     ant.  The -J option is a non-standard FreeBSD extension which may not be
     available on other	operating systems.

     If	utility	attempts to invoke another command such	that the number	of
     arguments or the size of the environment is increased, it risks execvp(3)
     failing with E2BIG.

FreeBSD	11.1			  May 7, 2001			  FreeBSD 11.1


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