sp               2164 dxref.c            int file_stack [STACK_SIZE], sp = 0;
sp               2190 dxref.c        	    if (sp >= STACK_SIZE) {
sp               2194 dxref.c        	    if (sp == 0) {
sp               2245 dxref.c        	    file_stack [sp++] = atoi (file_num);
sp               2247 dxref.c        					    file_stack [sp - 1]);
sp               2249 dxref.c        					    file_stack [sp - 1]);
sp               2251 dxref.c        	    if (sp < 2) {
sp               2257 dxref.c        						       file_stack [sp - 2]);
sp               2259 dxref.c        						       file_stack [sp - 2]);
sp               2284 dxref.c        						  file_stack [sp - 1]);
sp               2285 dxref.c        	    if (sp < 0) {
sp               2289 dxref.c        	    sp--;
sp               2297 dxref.c        						  file_stack [sp - 1]);
sp               2299 dxref.c        						  file_stack [sp - 1]);
sp               2328 dxref.c        						  file_stack [sp - 1]);
sp               2330 dxref.c        						  file_stack [sp - 1]);