src/user/touch.nsc

include "syscalls.nsh";
include "lib.nsh";
include "string.nsh";
include "stdio.nsh";
 
/* creates name (a bare name or a real path) if it doesn't already
 * exist -- a no-op, not an error, if it does. kfs has no mtime field
 * on an inode at all yet, so unlike real touch this can't update an
 * existing file's timestamp; "make sure this file exists" is the
 * whole feature for now. */
global i32
main(i32 argc, ptr argv)
{
	ptr name;
	u64 name_len;
	i64 kind;
 
	if(argc < 2)
	{
		fputs(2, "usage: touch name\n");
		return 1;
	}
 
	name = argv_get(argv, 1);
	name_len = strlen(name);
	kind = sys_stat(name, name_len);
	if(kind >= (i64)0)
	{
		return 0; /* already exists -- nothing to do */
	}
	if(sys_writefile(name, name_len, "", (u64)0) == 0)
	{
		print_err(2, "touch", "failed");
		return 1;
	}
	return 0;
}