diff '--color=auto' -ur a/src/vdcomp.c b/src/vdcomp.c
--- a/src/vdcomp.c	2024-07-17 09:37:04.957769272 -0500
+++ b/src/vdcomp.c	2024-07-17 09:44:30.582594953 -0500
@@ -130,6 +130,8 @@
 
 #    if defined(hp300) || defined(hp800) || defined(NeXT)
 #      include <sys/malloc.h>    /* it's in "sys" on HPs and NeXT */
+#    elif defined(__APPLE__)
+#      include <malloc/malloc.h>
 #    else
 #      include <malloc.h>        /* FIXME: should explicitly list systems that NEED this, not everyone that doesn't */
 #    endif
diff '--color=auto' -ur a/src/xv.h b/src/xv.h
--- a/src/xv.h	2024-07-17 09:37:04.957769272 -0500
+++ b/src/xv.h	2024-07-17 09:41:42.912041683 -0500
@@ -183,7 +183,7 @@
 
 #ifndef VMS
 #  include <errno.h>
-#  ifndef __NetBSD__
+#  if !defined(__NetBSD__) && !defined(__FreeBSD__) && !defined(__APPLE__)
 #    if !(defined(__GLIBC__) && __GLIBC__ >= 2) && !defined(__OpenBSD__)
        extern int   errno;         /* SHOULD be in errno.h, but often isn't */
 #      ifndef XV_HAVE_SYSERRLISTDECL
@@ -199,7 +199,7 @@
 #  ifdef VMS
 #    define ERRSTR(x) strerror(x, vaxc$errno)
 #  else
-#    if defined(__BEOS__) || defined(__linux__) /* or all modern/glibc systems? */
+#    if defined(__BEOS__) || defined(__linux__) || defined(__APPLE__) /* or all modern/glibc systems? */
 #      define ERRSTR(x) strerror(x)
 #    else
 #      define ERRSTR(x) sys_errlist[x]
@@ -236,6 +236,8 @@
 #ifdef NEED_MALLOC_H
 #  if defined(hp300) || defined(hp800) || defined(NeXT)
 #    include <sys/malloc.h>    /* it's in "sys" on HPs and NeXT */
+#  elif defined(__APPLE__)
+#   include <malloc/malloc.h>
 #  else
 #    include <malloc.h>
 #  endif
@@ -399,7 +401,7 @@
  *                them later. */
 #ifndef VMS       /* VMS hates multi-line definitions */
 #  if defined(__linux__) || defined(__OpenBSD__) || defined(__NetBSD__) || \
-      defined(__bsdi__)
+      defined(__FreeBSD__) || defined(__bsdi__) || defined(__APPLE__)
 #    ifndef USE_MKSTEMP
 #      define USE_MKSTEMP       /* use 'mkstemp()' instead of 'mktemp()' */
 #    endif                      /* >> SECURITY ISSUE << */