/* LATER.C -- Exit with a 1 if any file has a higher create
date than the last or if the last file does not exist.
A 2 is returned if any other files do not exist.
Later only works on MS-DOS V2.0.
A>LATER FILE1.C FILE1.O
Later will set completion code to 1 if FILE1.C was
created after FILE1.O.
A>LATER FILE1.C FILE1.H FILE1.O
Later will set completion code to 1 if FILE1.C or
FILE1.H was created after FILE1.O. */
main(argc,argv)
int argc;
char *argv[]; {
unsigned ifile,ofile,i;
long odate,dateof();
puts("LATER V1.0 ");
if (argc < 3 ) {
puts("need two or more arguments");
exit(0);
}
if ((ofile=open(argv[argc-1],0)) == -1)
exit(1); /* the last file does not exist */
odate=dateof(ofile);
close(ofile);
/* for each file see if it is later than the last one */
for (i=1; i < argc-1; i++) {
if ((ifile=open(argv[i],0)) == -1) {
puts(argv[i]);
puts(" does not exist");
exit(2); /* an early file does not exist */
}
if (dateof(ifile) > odate) exit(1); /* found a later file */
close(ifile);
}
/* none of the files are later. set completion code of zero */
exit(0);
}
/* return a long encoding the date and time of a file */
long dateof(fil)
int fil; {
static long ret_dt;
#asm
mov bx,[bp+4] ;file handle is here. only argument.
and bx,0ffh ;low byte of file id is MS-DOS handle.
mov al,0 ;code to retrieve date and time.
mov ah,57h ;dos code for get file date and time.
int 21h ;call dos.
mov word dateof_ret_dt_+2,dx;store date in high word of ret_dt.
mov word dateof_ret_dt_,cx ;store time in low word of ret_dt.
;note: "dateof_" is added to name
;because ret_dt is static.
#
return ret_dt;
}
