diff -ru pl240src/src.broken/proc_annotate.c pl240src/src/proc_annotate.c
--- pl240src/src.broken/proc_annotate.c	2007-11-23 15:24:57.000000000 -0500
+++ pl240src/src/proc_annotate.c	2008-03-27 14:48:38.000000000 -0400
@@ -141,7 +141,7 @@
 	}
 else do_arrows();
 
-if( PLS.clickmap && (mapurl != "" || maplabel != "" )) {
+if( PLS.clickmap && ((mapurl && *mapurl) || (maplabel && *maplabel) )) {
 	if( backdim && do_ellipse ) {
 		/* need to solve back to ulx,uly in this case.. */
 		ulx = (((boxw/2.0)-cx)*-1.0); 
diff -ru pl240src/src.broken/proc_areadef.c pl240src/src/proc_areadef.c
--- pl240src/src.broken/proc_areadef.c	2008-01-14 11:14:51.000000000 -0500
+++ pl240src/src/proc_areadef.c	2008-03-27 14:48:45.000000000 -0400
@@ -328,7 +328,7 @@
 
 
 if( areacolor[0] != '\0' ) Ecblock( EXlo, EYlo, EXhi, EYhi, areacolor, 0 );
-if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) {  
+if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) {  
 	PL_clickmap_adjust( clickmap_adjx, clickmap_adjy ); /* set adjustment, if any.  added scg 10/24/06 */
 	if( GL_slmember( mapurl, "*@XVAL*" ) || GL_slmember( mapurl, "*@YVAL*" )) clickmap_seturlt( mapurl );
 	else clickmap_entry( 'r', mapurl, 0, EXlo, EYlo, EXhi, EYhi, 0, 0, maplabel );
diff -ru pl240src/src.broken/proc_bars.c pl240src/src/proc_bars.c
--- pl240src/src.broken/proc_bars.c	2008-01-09 15:19:43.000000000 -0500
+++ pl240src/src/proc_bars.c	2008-03-27 14:46:57.000000000 -0400
@@ -438,7 +438,7 @@
 	/* now do the bar.. */
 
 	/* allow @field substitutions into url */
-	if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) {
+	if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) {
 		expandedurl = PL_bigbuf;
 		expandedlabel = &PL_bigbuf[2000];
 		do_subst( expandedurl, mapurl, irow, URL_ENCODED );
@@ -465,7 +465,7 @@
 			if( y0_endin ) Elin( xleft, Ea( Y, y0 ) );
 			}
 
-		if( PLS.clickmap && (mapurl != "" || maplabel != "" )) {
+		if( PLS.clickmap && ((mapurl && *mapurl) || (maplabel && *maplabel))) {
 			if( Eflip ) clickmap_entry( 'r', expandedurl, 0, Ea( Y, y0 ), xleft, Ea( Y, y ), xright, 0, 0, expandedlabel );
 			else clickmap_entry( 'r', expandedurl, 0, xleft, Ea( Y, y0 ), xright, Ea( Y, y ), 0, 0, expandedlabel );
 			}
diff -ru pl240src/src.broken/proc_categories.c pl240src/src/proc_categories.c
--- pl240src/src.broken/proc_categories.c	2008-01-11 16:14:30.000000000 -0500
+++ pl240src/src/proc_categories.c	2008-03-27 14:50:37.000000000 -0400
@@ -94,7 +94,7 @@
 	sprintf( buf, "datafield=%s %s%s", catspec, (selectex[0]=='\0')?"":"selectrows=", selectex );  /* combine with selectex */
 	catspec = buf;  /* make catspec point to the whole thing.. */
 	}
-if( catspec != "" ) PL_setcats( axis, catspec );
+if( catspec && *catspec ) PL_setcats( axis, catspec );
 
 /* things to be done after filling list.. */
 for( i = 0; i < nextra; i++ ) if( ecattype[i] == '>' ) PL_addcat( axis, "post", ecat[i] );  /* post- extras */
diff -ru pl240src/src.broken/proc_drawcommands.c pl240src/src/proc_drawcommands.c
--- pl240src/src.broken/proc_drawcommands.c	2007-11-23 16:40:38.000000000 -0500
+++ pl240src/src/proc_drawcommands.c	2008-03-27 14:49:16.000000000 -0400
@@ -50,7 +50,7 @@
 /* -------------------------- */
 /* now do the plotting work.. */
 /* -------------------------- */
-if( commands != "" ) {
+if( commands && *commands ) {
 	sprintf( buf, "%s_Z", PLS.tmpname );
 	fp = fopen( buf, "w" ); /* temp file, unlinked below */
 	if( fp == NULL ) return( Eerr( 522, "Cannot open draw commands file", buf ));
@@ -60,9 +60,9 @@
 	unlink( buf );
 	}
 
-else if( dcfile != "" ) do_drawcommands( dcfile );
+else if( dcfile && *dcfile ) do_drawcommands( dcfile );
 
-else if( dumpfile != "" ) {
+else if( dumpfile && *dumpfile ) {
 	fp = fopen( dumpfile, "r" );
 	if( fp == NULL ) return( Eerr( 523, "Cannot open dump file", dumpfile ) );
 	while( fgets( buf, 1023, fp ) != NULL ) {
diff -ru pl240src/src.broken/proc_getdata.c pl240src/src/proc_getdata.c
--- pl240src/src.broken/proc_getdata.c	2008-01-11 15:13:44.000000000 -0500
+++ pl240src/src/proc_getdata.c	2008-03-27 14:53:37.000000000 -0400
@@ -369,7 +369,7 @@
 READ_DONE:
 
 PL_finishdataset( nrecords, nfields );
-if( nscriptrows > 0 && pfnames != "" ) definefieldnames( pfnames ); /* assign any post-filter field names.. */
+if( nscriptrows > 0 && pfnames && *pfnames ) definefieldnames( pfnames ); /* assign any post-filter field names.. */
 
 if( showdata ) {
         getfname( 1, buf );
diff -ru pl240src/src.broken/proc_image.c pl240src/src/proc_image.c
--- pl240src/src.broken/proc_image.c	2007-11-23 16:42:06.000000000 -0500
+++ pl240src/src/proc_image.c	2008-03-27 14:50:28.000000000 -0400
@@ -50,7 +50,7 @@
  * for SVG, image alignment (centering, etc) is done here, and image width and height must be given in order to do alignment.
  */
 
-if( filename == "" ) return( Eerr( 72509, "image file not specified", "" ));
+if( !filename || !*filename ) return( Eerr( 72509, "image file not specified", "" ));
 
 if( height == 0 || width == 0 ) {
 	Eerr( 75935, "warning, image height and width (in pixels) expected but not specified", "" );
@@ -81,7 +81,7 @@
         Emov( x, y ); Elin( x+aw, y ); Elin( x+aw, y-ah );  Elin( x, y-ah ); Elin( x, y );
 	}
 
-if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) clickmap_entry( 'r', mapurl, 0, x, y-ah, x+aw, y, 0, 0, maplabel );
+if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) clickmap_entry( 'r', mapurl, 0, x, y-ah, x+aw, y, 0, 0, maplabel );
 
 return( 0 );
 }
diff -ru pl240src/src.broken/proc_legend.c pl240src/src/proc_legend.c
--- pl240src/src.broken/proc_legend.c	2007-11-28 15:31:50.000000000 -0500
+++ pl240src/src/proc_legend.c	2008-03-27 14:48:57.000000000 -0400
@@ -170,7 +170,7 @@
 
 	/* fprintf( stderr, "%d|%s|%s|%s\n", LEtype[i], &Ltext[LElabel[i]], &Ltext[LEparm1[i]], &Ltext[LEparm2[i]] ); */
 
-	if( specifyorder != "" ) {
+	if( specifyorder && *specifyorder ) {
 		/* get next line in orderspec.. */
 		NEXTORDERLINE:
 		GL_getchunk( buf, specifyorder, &ix, "\n" );
diff -ru pl240src/src.broken/proc_pie.c pl240src/src/proc_pie.c
--- pl240src/src.broken/proc_pie.c	2007-11-23 16:51:57.000000000 -0500
+++ pl240src/src/proc_pie.c	2008-03-27 14:48:28.000000000 -0400
@@ -221,7 +221,7 @@
 			if( PLS.bignumspacer ) rewritenums( pctstr ); /* added 4/5/03 */
 
 			if( lblfld >= 0 ) strcpy( lbl, da( irow, lblfld ) );
-			else if( labels != "" ) GL_getseg( lbl, labels, &ibb, "\n" );
+			else if( labels && *labels ) GL_getseg( lbl, labels, &ibb, "\n" );
 			else if( lblfmtstring[0] != '\0' ) { /* added scg 8/20/04 */
 				strcpy( buf, lblfmtstring );
 				GL_varsub( buf, "@PCT", pctstr );
@@ -232,7 +232,7 @@
 			convertnl( lbl );
 
 			/* allow @field substitutions into url */
-			if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) {
+			if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) {
 				expandedurl = PL_bigbuf;
 				expandedlabel = &PL_bigbuf[2000];
 				do_subst( expandedurl, mapurl, irow, URL_ENCODED );
@@ -265,14 +265,14 @@
 				else { x1 = labx; x2 = labx + boxwid; }
 				y1 = laby-boxhi; y2 = laby;
 
-				if( labelback != "" ) Ecblock( x1-0.1, y1+(Ecurtextheight*0.6), x2+0.1, y2+Ecurtextheight, labelback, labelbackoutline );
+				if( labelback && *labelback ) Ecblock( x1-0.1, y1+(Ecurtextheight*0.6), x2+0.1, y2+Ecurtextheight, labelback, labelbackoutline );
 
 				textdet( "textdetails", textdetails, &align, &adjx, &adjy, -2,"R", 1.0 );
 				Emov( labx, laby );
 				if( !centerit && x < cx ) Erightjust( lbl );
 				else if( !centerit && x >= cx ) Etext( lbl );
 				else Ecentext( lbl );
-				if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) 
+				if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) 
 					clickmap_entry( 'r', expandedurl, 0, x1, y1+Ecurtextheight, x2, y2+Ecurtextheight, 1, 0, expandedlabel );
 				linedet( "linedetails", outlinedetails, 0.5 ); /* restore */
 				}
@@ -311,7 +311,7 @@
 
 					Emov( labx, laby );
 					Erightjust( lbl );
-					if( PLS.clickmap && ( mapurl != "" || maplabel != "" ))
+					if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) ))
 						clickmap_entry( 'r', expandedurl, 0, labx-boxwid, laby-boxhi+Ecurtextheight, 
 							labx, laby+Ecurtextheight, 1, 0, expandedlabel );
 						
@@ -326,7 +326,7 @@
 							labx+boxwid+0.1, laby+Ecurtextheight, labelback, labelbackoutline );
 					Emov( labx, laby );
 					Etext( lbl );
-					if( PLS.clickmap && ( mapurl != "" || maplabel != "" ))
+					if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) ))
 						clickmap_entry( 'r', expandedurl, 0, labx, laby-boxhi+Ecurtextheight, 
 							labx+boxwid, laby+Ecurtextheight, 1, 0, expandedlabel );
 
diff -ru pl240src/src.broken/proc_processdata.c pl240src/src/proc_processdata.c
--- pl240src/src.broken/proc_processdata.c	2007-11-28 16:18:01.000000000 -0500
+++ pl240src/src/proc_processdata.c	2008-03-27 14:50:03.000000000 -0400
@@ -166,7 +166,7 @@
 	}
 for( i = 0; i < MAXFLD; i++ ) accum[i] = 0.0;
 
-if( outfile == "" ) {
+if( !outfile || !*outfile ) {
 	stat = PL_begindataset(); 
 	if( stat != 0 ) return( stat );
 	}
@@ -377,7 +377,7 @@
 	               	if( select_result == 0 || stat ) continue; /* reject */
 	               	}
 
-		if( binsize != "" ) {
+		if( binsize && *binsize ) {
 			fbin = atof( binsize );
 			if( fbin != 0.0 ) {
 				fval = atof( da( i, fld[0] ));
@@ -811,10 +811,10 @@
 	if( strncmp( action, "tot", 3 )==0 ) return( 0 );
 	}
 
-if( outfile != "" ) fclose( outfp );
+if( outfile && *outfile ) fclose( outfp );
 else PL_finishdataset( 0, 0 );
 
-if( fieldnames != "" ) definefieldnames( fieldnames ); 
+if( fieldnames && *fieldnames ) definefieldnames( fieldnames ); 
 
 if( showdata ) {
 	getfname( 1, buf );
@@ -861,7 +861,7 @@
 static int 
 bor( )
 {
-if( outfile == "" ) return( PL_startdatarow() );
+if( !outfile || !*outfile ) return( PL_startdatarow() );
 else return( 0 );
 }
 
@@ -869,7 +869,7 @@
 out( s )
 char *s;
 {
-if( outfile != "" ) fprintf( outfp, "%s	", s );
+if( outfile && *outfile ) fprintf( outfp, "%s	", s );
 else PL_catitem( s );
 return( 0 );
 }
@@ -877,7 +877,7 @@
 static int
 eor()
 {
-if( outfile != "" ) fprintf( outfp, "\n" );
+if( outfile && *outfile ) fprintf( outfp, "\n" );
 else PL_enddatarow(); 
 return( 0 );
 }
diff -ru pl240src/src.broken/proc_rect.c pl240src/src/proc_rect.c
--- pl240src/src.broken/proc_rect.c	2007-11-23 17:08:49.000000000 -0500
+++ pl240src/src/proc_rect.c	2008-03-27 14:50:13.000000000 -0400
@@ -63,7 +63,7 @@
 if( bevelsize > 0.0 || shadowsize > 0.0 ) 
 	Ecblockdress( xlo, ylo, xhi, yhi, bevelsize, lowbevelcolor, hibevelcolor, shadowsize, shadowcolor);
 
-if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) clickmap_entry( 'r', mapurl, 0, xlo, ylo, xhi, yhi, 0, 0, maplabel );
+if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) clickmap_entry( 'r', mapurl, 0, xlo, ylo, xhi, yhi, 0, 0, maplabel );
 
 return( 0 );
 }
diff -ru pl240src/src.broken/proc_scatterplot.c pl240src/src/proc_scatterplot.c
--- pl240src/src.broken/proc_scatterplot.c	2007-11-23 16:54:31.000000000 -0500
+++ pl240src/src/proc_scatterplot.c	2008-03-27 14:51:48.000000000 -0400
@@ -87,7 +87,7 @@
 	else if( strcmp( attr, "clickmaplabel" )==0 ) maplabel = lineval;
         else if( strcmp( attr, "clickmaplabeltext" )==0 ) maplabel = getmultiline( lineval, "get" ); 
 	else if( strcmp( attr, "linelen" )==0 ) {
-		if( lineval == "" ) linelen = -1.0;
+		if( !lineval || !*lineval ) linelen = -1.0;
 		else	{ linelen = ftokncpy( lineval ); if( PLS.usingcm ) linelen /= 2.54; }
 		}
 	else if( strcmp( attr, "linedir" )==0 ) reqlinedir = lineval[0];
@@ -256,7 +256,7 @@
 /* in the following, text must come before symbol.. */
 if( text[0] != '\0' || lblfield >= 0 )  textdet( "textdetails", textdetails, &align, &adjx, &adjy, -3, "R", 1.0 );
 	
-if( symbol != "" ) symdet( "symbol", symbol, symcode, &radius );
+if( symbol && *symbol ) symdet( "symbol", symbol, symcode, &radius );
 	
 if( linelen > 0.0 || rectoutline )  linedet( "linedetails", linedetails, 0.5 );
 	
@@ -317,7 +317,7 @@
 		}
 
 	/* allow @field substitutions into url */
-        if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) {
+        if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) {
 		expandedurl = &PL_bigbuf[0];
 		expandedlabel = &PL_bigbuf[2000];
 		do_subst( expandedurl, mapurl, realrow, URL_ENCODED );
@@ -330,16 +330,16 @@
 	/* text can be combined with mark if text and symbol both specified */
 
 	/* symbol or rectangle.. */
-	if( symbol != "" || dorect || ( text[0] == '\0' && linelen <= 0.0 && lblfield < 0 ) ) {
+	if( (symbol && *symbol) || dorect || ( text[0] == '\0' && linelen <= 0.0 && lblfield < 0 ) ) {
 		if( symfield >= 0 ) {  /* look it up in legend list.. */
 			if( symfield_userange ) symbol = PL_get_legent_rg( atof( da( realrow, symfield ) ) );
                 	else symbol = PL_get_legent( da( realrow, symfield ));
-			if( symbol == "" ) Eerr( 7429, "warning: symfield: no matching legend entry tag found", da( realrow, symfield ) );
+			if( !symbol || !*symbol ) Eerr( 7429, "warning: symfield: no matching legend entry tag found", da( realrow, symfield ) );
 			if( !dorect ) symdet( "symfield", symbol, symcode, &radius );
 			}
 		if( dupsleg ) {  /* look it up in legend list.. */
                 	symbol = PL_get_legent_rg( (double)dupcount+1 );
-			if( symbol == "" ) Eerr( 7692, "warning: dupsleg: no appropriate legend entry tag\n", da( realrow, symfield ) );
+			if( !symbol || !*symbol ) Eerr( 7692, "warning: dupsleg: no appropriate legend entry tag\n", da( realrow, symfield ) );
 			if( !dorect ) symdet( "symfield", symbol, symcode, &radius );
 			/* note: currently all marks will be rendered; the last one will be on "top"  */
 			}
@@ -373,7 +373,7 @@
 			if( doing_alt == 1 ) symdet( "symbol", symbol, symcode, &radius );  /* restore */
 			}
 
-		if( PLS.clickmap && (mapurl != "" || maplabel != "" )) {
+		if( PLS.clickmap && ((mapurl && *mapurl) || (maplabel && *maplabel) )) {
 			if( dorect ) clickmap_entry( 'r', expandedurl, 0, x-rectw, y-recth, x+rectw, y+recth, 0, 0, expandedlabel );
 			else clickmap_entry( 'r', expandedurl, 0, x-radius, y-radius, x+radius, y+radius, 0, 0, expandedlabel );
 			}
@@ -382,7 +382,7 @@
 
 	/* text */
 	if( text[0] != '\0' ) {
-		if( symbol != "" )  /* set text color etc... */
+		if( symbol && *symbol )  /* set text color etc... */
 			textdet( "textdetails", textdetails, &align, &adjx, &adjy, -3, "R", 1.0 );
 		if( sizefield >= 0 ) Etextsize( (int) (atof( da( realrow, sizefield ) ) * sizescale) );
 		if( verttext ) { ptx = (x+cy)+adjx; pty = y; } /* cy puts midheight of character on point */
@@ -392,10 +392,10 @@
 		Emov( ptx, pty );
 		if( align == '?' ) Edotext( text, 'C' );
 		else Edotext( text, align );
-		if( symbol != ""  )  /* restore symbol color etc... */
+		if( symbol && *symbol  )  /* restore symbol color etc... */
 			symdet( "symbol", symbol, symcode, &radius );
 
-		if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) 
+		if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) 
 			clickmap_entry( 'r', expandedurl, 0, ptx-hw, pty, x+hw, y+txhi, 0, 0, expandedlabel );
 		}
 
@@ -412,7 +412,7 @@
 		if( align == '?' ) Edotext( buf, 'C' );
 		else Edotext( buf, align );
 
-		if( PLS.clickmap && ( mapurl != "" || maplabel != "" )) {
+		if( PLS.clickmap && ( (mapurl && *mapurl) || (maplabel && *maplabel) )) {
 			hw = strlen( buf ) * Ecurtextwidth * 0.5;
 			if( GL_member( align, "C?" ))clickmap_entry( 'r', expandedurl, 0, ptx-hw, pty, x+hw, y+txhi, 0, 0, expandedlabel );
 			else if( align == 'L' ) clickmap_entry( 'r', expandedurl, 0, ptx, pty, x+(hw*2.0), y+txhi, 0, 0, expandedlabel );
@@ -445,7 +445,7 @@
 	GL_varsub( legendlabel, "@NVALUES", s );
 	if( linelen <= 0.0 && lblfield < 0 && text[0] == '\0' )
 		PL_add_legent( LEGEND_SYMBOL, legendlabel, "", symbol, "", "" );
-	else if( symbol != "" && text[0] != '\0' )
+	else if( symbol && *symbol && text[0] != '\0' )
 		PL_add_legent( LEGEND_SYMBOL+LEGEND_TEXT, legendlabel, "", text, textdetails, symbol );
 	else if( linelen > 0.0 ) {
 		char dirstr[8];