Stick two directories and a file name together. */
zsappend3 (zdir1
, zdir2
, zfile
)
size_t cdir1
, cdir2
, cfile
;
zret
= zbufalc (cdir1
+ cdir2
+ cfile
+ 3);
memcpy (zret
, zdir1
, cdir1
);
memcpy (zret
+ cdir1
+ 1, zdir2
, cdir2
);
memcpy (zret
+ cdir1
+ cdir2
+ 2, zfile
, cfile
);
zret
[cdir1
+ cdir2
+ 1] = '/';
zret
[cdir1
+ cdir2
+ cfile
+ 2] = '\0';