	INTEGER*4 FUNCTION ALLO_MANAGED_GRID ( islot )

*
*
*  This software was developed by the Thermal Modeling and Analysis
*  Project(TMAP) of the National Oceanographic and Atmospheric
*  Administration's (NOAA) Pacific Marine Environmental Lab(PMEL),
*  hereafter referred to as NOAA/PMEL/TMAP.
*
*  Access and use of this software shall impose the following
*  obligations and understandings on the user. The user is granted the
*  right, without any fee or cost, to use, copy, modify, alter, enhance
*  and distribute this software, and any derivative works thereof, and
*  its supporting documentation for any purpose whatsoever, provided
*  that this entire notice appears in all copies of the software,
*  derivative works and supporting documentation.  Further, the user
*  agrees to credit NOAA/PMEL/TMAP in any publications that result from
*  the use of this software or in any product that includes this
*  software. The names TMAP, NOAA and/or PMEL, however, may not be used
*  in any advertising or publicity to endorse or promote any products
*  or commercial entity unless specific written permission is obtained
*  from NOAA/PMEL/TMAP. The user also understands that NOAA/PMEL/TMAP
*  is not obligated to provide the user with any support, consulting,
*  training or assistance of any kind with regard to the use, operation
*  and performance of this software nor to provide the user with any
*  updates, revisions, new versions or "bug fixes".
*
*  THIS SOFTWARE IS PROVIDED BY NOAA/PMEL/TMAP "AS IS" AND ANY EXPRESS
*  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
*  ARE DISCLAIMED. IN NO EVENT SHALL NOAA/PMEL/TMAP BE LIABLE FOR ANY SPECIAL,
*  INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
*  RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
*  CONTRACT, NEGLIGENCE OR OTHER TORTUOUS ACTION, ARISING OUT OF OR IN
*  CONNECTION WITH THE ACCESS, USE OR PERFORMANCE OF THIS SOFTWARE. 
*
*
* Locates an unused grid slot and returns it.
* This routine parallels TM_FIND_GRID_SLOT in function but whereas that
* routine allocates from lower memory in grid common and leaves gaps
* as grids are deleted this routine allocates from upper memory and uses
* linked lists to maintain integrity.
* If no grid slot is available this returns returns error.

* This code is a temporary version that does NOT use linked lists.  Instead
* it simply locates the first available grid slot starting from position one.
* By contrast TM_FIND_GRID_SLOT locates the beginning of the upper contiguous
* grid storage space

* This routine functions as a part of the TMAP library

* for FERRET version 4.00 8/94  *sh*
*Linux Port 1/97 *kob* - Added a preprocessor include for tmap_dset.parm
*			  because it needed a preprocessor.
*       *acm* 3/12 cleanup ifdefs and unnecessary include files

        IMPLICIT NONE
* Arguments
	INTEGER*4	islot
*
* Parameters and commons
	include	'tmap_dims.parm'
#	include	"tmap_dset.parm"
	include	'tmap_errors.parm'
	include 'xtm_grid.cmn_text'
	external xgt_grid_data
	include	'xfr_grid.cmn'			! fr200
*
* Local declarations
	CHARACTER*13	TM_STRING
	INTEGER status

	DO 100 islot = 1, grd_stk_ptr-1
	  IF (grid_name(islot) .EQ. char_init16) THEN
	     ALLO_MANAGED_GRID = merr_ok
	     RETURN
	  ENDIF
  100	CONTINUE


* No slot available
 9000	CALL TM_ERRMSG (merr_gridlim, status,
     .	                'ALLO_MANAGED_GRID', no_descfile, no_stepfile,
     .	                'MAX='//TM_STRING(DBLE(max_grids)), no_errstring,
     .	                *9999)


 9999	ALLO_MANAGED_GRID = status
	RETURN
	END
