Stick three directories and a file name together. */
zsappend4 (zdir1
, zdir2
, zdir3
, zfile
)
size_t cdir1
, cdir2
, cdir3
, cfile
;
zret
= zbufalc (cdir1
+ cdir2
+ cdir3
+ cfile
+ 4);
memcpy (zret
, zdir1
, cdir1
);
memcpy (zret
+ cdir1
+ 1, zdir2
, cdir2
);
memcpy (zret
+ cdir1
+ cdir2
+ 2, zdir3
, cdir3
);
memcpy (zret
+ cdir1
+ cdir2
+ cdir3
+ 3, zfile
, cfile
);
zret
[cdir1
+ cdir2
+ 1] = '/';
zret
[cdir1
+ cdir2
+ cdir3
+ 2] = '/';
zret
[cdir1
+ cdir2
+ cdir3
+ cfile
+ 3] = '\0';