collapseos/tools/slatest.c
Virgil Dupras 9235fa9223 Add /tools/slatest
To update LATEST offset more easily. Will be useful for recipes.
2020-04-02 23:20:47 -04:00

30 lines
665 B
C

#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
/* Update the "LATEST" offset of target Forth binary according to filesize. */
#define OFFSET 0x08
int main(int argc, char **argv)
{
if (argc != 2) {
fprintf(stderr, "Usage: ./slatest fname\n");
return 1;
}
FILE *fp = fopen(argv[1], "r+");
if (!fp) {
fprintf(stderr, "Can't open %s.\n", argv[1]);
return 1;
}
fseek(fp, 0, SEEK_END);
unsigned int bytecount = ftell(fp);
fseek(fp, OFFSET, SEEK_SET);
char buf[2];
buf[0] = bytecount & 0xff;
buf[1] = bytecount >> 8;
fwrite(buf, 2, 1, fp);
fclose(fp);
}