diff -ruwN bash-5.2.15/bashline.c source/bashline.c
--- bash-5.2.15/bashline.c	2022-04-17 16:37:12.000000000 -0600
+++ source/bashline.c	2023-09-09 09:07:14.698070413 -0600
@@ -2645,7 +2645,7 @@
      const char *text;
      int state;
 {
-#if defined (__WIN32__) || defined (__OPENNT) || !defined (HAVE_GRP_H)
+#if defined (__WIN32__) || defined (__OPENNT) || !defined (HAVE_GRP_H) || defined(__redox__)
   return ((char *)NULL);
 #else
   static char *gname = (char *)NULL;
diff -ruwN bash-5.2.15/builtins/ulimit.def source/builtins/ulimit.def
--- bash-5.2.15/builtins/ulimit.def	2021-11-05 07:19:53.000000000 -0600
+++ source/builtins/ulimit.def	2023-09-09 09:07:14.698070413 -0600
@@ -609,7 +609,7 @@
       }
   else
     {
-#if defined (HAVE_RESOURCE)
+#if defined (HAVE_RESOURCE) && !defined(__redox__)
       if (getrlimit (limits[ind].parameter, &limit) < 0)
 	return -1;
 #  if defined (HPUX9)
diff -ruwN bash-5.2.15/config-top.h source/config-top.h
--- bash-5.2.15/config-top.h	2021-11-05 07:11:12.000000000 -0600
+++ source/config-top.h	2023-09-09 09:07:14.698070413 -0600
@@ -63,24 +63,24 @@
 /* The default value of the PATH variable. */
 #ifndef DEFAULT_PATH_VALUE
 #define DEFAULT_PATH_VALUE \
-  "/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin:."
+  "/usr/local/bin;/usr/local/sbin;/usr/bin;/usr/sbin;/bin;/sbin;."
 #endif
 
 /* If you want to unconditionally set a value for PATH in every restricted
    shell, set this. */
-/* #define RBASH_STATIC_PATH_VALUE "/rbin:/usr/rbin" */
+/* #define RBASH_STATIC_PATH_VALUE "/rbin;/usr/rbin" */
 
 /* The value for PATH when invoking `command -p'.  This is only used when
    the Posix.2 confstr () function, or CS_PATH define are not present. */
 #ifndef STANDARD_UTILS_PATH
 #define STANDARD_UTILS_PATH \
-  "/bin:/usr/bin:/sbin:/usr/sbin:/etc:/usr/etc"
+  "/bin;/usr/bin;/sbin;/usr/sbin;/etc;/usr/etc"
 #endif
 
 /* The default path for enable -f */
 #ifndef DEFAULT_LOADABLE_BUILTINS_PATH
 #define DEFAULT_LOADABLE_BUILTINS_PATH \
-  "/usr/local/lib/bash:/usr/lib/bash:/opt/local/lib/bash:/usr/pkg/lib/bash:/opt/pkg/lib/bash:."
+  "/usr/local/lib/bash;/usr/lib/bash;/opt/local/lib/bash;/usr/pkg/lib/bash;/opt/pkg/lib/bash;."
 #endif
 
 /* Default primary and secondary prompt strings. */
diff -ruwN bash-5.2.15/configure source/configure
--- bash-5.2.15/configure	2022-09-23 08:13:22.000000000 -0600
+++ source/configure	2023-09-09 09:07:14.702070414 -0600
@@ -3298,6 +3298,7 @@
 *-nsk*)		opt_bash_malloc=no ;;	# HP NonStop
 *-haiku*)	opt_bash_malloc=no ;;	# Haiku OS
 *-genode*)	opt_bash_malloc=no ;;	# Genode has no sbrk
+*-redox*)	opt_bash_malloc=no ;;	# Redox OS
 esac
 
 # memory scrambling on free()
diff -ruwN bash-5.2.15/configure.ac source/configure.ac
--- bash-5.2.15/configure.ac	2022-09-23 08:12:27.000000000 -0600
+++ source/configure.ac	2023-09-09 09:07:14.702070414 -0600
@@ -92,6 +92,7 @@
 *-nsk*)		opt_bash_malloc=no ;;	# HP NonStop
 *-haiku*)	opt_bash_malloc=no ;;	# Haiku OS
 *-genode*)	opt_bash_malloc=no ;;	# Genode has no sbrk
+*-redox*)	opt_bash_malloc=no ;;	# Redox OS
 esac
 
 # memory scrambling on free()
diff -ruwN bash-5.2.15/execute_cmd.c source/execute_cmd.c
--- bash-5.2.15/execute_cmd.c	2022-12-13 10:09:02.000000000 -0700
+++ source/execute_cmd.c	2023-09-09 09:07:14.702070414 -0600
@@ -1379,11 +1379,11 @@
   nullcmd = (command == 0) || (command->type == cm_simple && command->value.Simple->words == 0 && command->value.Simple->redirects == 0);
   if (posixly_correct && nullcmd)
     {
-#if defined (HAVE_GETRUSAGE)
+#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY)
       selfb.ru_utime.tv_sec = kidsb.ru_utime.tv_sec = selfb.ru_stime.tv_sec = kidsb.ru_stime.tv_sec = 0;
       selfb.ru_utime.tv_usec = kidsb.ru_utime.tv_usec = selfb.ru_stime.tv_usec = kidsb.ru_stime.tv_usec = 0;
       before = shellstart;
-#else
+#elif defined (HAVE_TIMES)
       before.tms_utime = before.tms_stime = before.tms_cutime = before.tms_cstime = 0;
       tbefore = shell_start_time;
 #endif
diff -ruwN bash-5.2.15/general.c source/general.c
--- bash-5.2.15/general.c	2022-11-23 15:10:12.000000000 -0700
+++ source/general.c	2023-09-09 09:07:14.702070414 -0600
@@ -589,6 +589,7 @@
 void
 check_dev_tty ()
 {
+#if !defined(__redox__)
   int tty_fd;
   char *tty;
 
@@ -603,6 +604,7 @@
     }
   if (tty_fd >= 0)
     close (tty_fd);
+#endif
 }
 
 /* Return 1 if PATH1 and PATH2 are the same file.  This is kind of
@@ -1031,10 +1033,10 @@
      `:'.  If I is 0, then the path has a leading colon.  Trailing colons
      are handled OK by the `else' part of the if statement; an empty
      string is returned in that case. */
-  if (i && string[i] == ':')
+  if (i && string[i] == ';')
     i++;
 
-  for (start = i; string[i] && string[i] != ':'; i++)
+  for (start = i; string[i] && string[i] != ';'; i++)
     ;
 
   *p_index = i;
diff -ruwN bash-5.2.15/include/posixwait.h source/include/posixwait.h
--- bash-5.2.15/include/posixwait.h	2019-03-29 11:25:52.000000000 -0600
+++ source/include/posixwait.h	2023-09-09 09:07:14.702070414 -0600
@@ -34,7 +34,7 @@
 
 /* How to get the status of a job.  For Posix, this is just an
    int, but for other systems we have to crack the union wait. */
-#if !defined (_POSIX_VERSION)
+#if 0
 typedef union wait WAIT;
 #  define WSTATUS(t)  (t.w_status)
 #else /* _POSIX_VERSION */
@@ -50,7 +50,7 @@
 
 /* More Posix P1003.1 definitions.  In the POSIX versions, the parameter is
    passed as an `int', in the non-POSIX version, as `union wait'. */
-#if defined (_POSIX_VERSION)
+#if 1
 
 #  if !defined (WSTOPSIG)
 #    define WSTOPSIG(s)       ((s) >> 8)
diff -ruwN bash-5.2.15/lib/readline/input.c source/lib/readline/input.c
--- bash-5.2.15/lib/readline/input.c	2022-04-08 13:43:24.000000000 -0600
+++ source/lib/readline/input.c	2023-09-09 09:07:14.702070414 -0600
@@ -805,7 +805,7 @@
   int result;
   unsigned char c;
   int fd;
-#if defined (HAVE_PSELECT)
+#if defined (HAVE_PSELECT) || defined (HAVE_SELECT)
   sigset_t empty_set;
   fd_set readfds;
 #endif
diff -ruwN bash-5.2.15/lib/readline/terminal.c source/lib/readline/terminal.c
--- bash-5.2.15/lib/readline/terminal.c	2022-04-05 08:44:17.000000000 -0600
+++ source/lib/readline/terminal.c	2023-09-09 09:09:03.162131539 -0600
@@ -102,7 +102,7 @@
 
 static int tcap_initialized;
 
-#if !defined (__linux__) && !defined (NCURSES_VERSION)
+#if !defined (__linux__) && !defined (NCURSES_VERSION) && !defined (__redox__)
 #  if defined (__EMX__) || defined (NEED_EXTERN_PC)
 extern 
 #  endif /* __EMX__ || NEED_EXTERN_PC */
diff -ruwN bash-5.2.15/lib/sh/getcwd.c source/lib/sh/getcwd.c
--- bash-5.2.15/lib/sh/getcwd.c	2012-03-10 08:48:50.000000000 -0700
+++ source/lib/sh/getcwd.c	2023-09-09 09:07:14.702070414 -0600
@@ -20,7 +20,7 @@
 
 #include <config.h>
 
-#if !defined (HAVE_GETCWD)
+#if !defined (HAVE_GETCWD) && !defined(__redox__)
 
 #if !defined (__GNUC__) && !defined (HAVE_ALLOCA_H) && defined (_AIX)
   #pragma alloca
diff -ruwN bash-5.2.15/lib/sh/input_avail.c source/lib/sh/input_avail.c
--- bash-5.2.15/lib/sh/input_avail.c	2021-05-24 09:16:33.000000000 -0600
+++ source/lib/sh/input_avail.c	2023-09-09 09:07:14.702070414 -0600
@@ -33,7 +33,7 @@
 #  include <sys/file.h>
 #endif /* HAVE_SYS_FILE_H */
 
-#if defined (HAVE_PSELECT)
+#if defined (HAVE_PSELECT) || defined (HAVE_SELECT)
 #  include <signal.h>
 #endif
 
diff -ruwN bash-5.2.15/lib/sh/strtoimax.c source/lib/sh/strtoimax.c
--- bash-5.2.15/lib/sh/strtoimax.c	2021-09-10 08:32:35.000000000 -0600
+++ source/lib/sh/strtoimax.c	2023-09-09 09:10:21.618185121 -0600
@@ -55,6 +55,8 @@
 extern long long strtoll PARAMS((const char *, char **, int));
 #endif
 
+#if !defined (__redox__)
+
 #ifdef strtoimax
 #undef strtoimax
 #endif
@@ -79,6 +81,8 @@
   return (strtol (ptr, endptr, base));
 }
 
+#endif
+
 #ifdef TESTING
 # include <stdio.h>
 int
diff -ruwN bash-5.2.15/parse.y source/parse.y
--- bash-5.2.15/parse.y	2022-12-13 10:09:02.000000000 -0700
+++ source/parse.y	2023-09-09 09:07:14.706070416 -0600
@@ -2625,6 +2625,7 @@
       parser_state |= PST_ENDALIAS;
       /* We need to do this to make sure last_shell_getc_is_singlebyte returns
 	 true, since we are returning a single-byte space. */
+#if defined (HANDLE_MULTIBYTE)
       if (shell_input_line_index == shell_input_line_len && last_shell_getc_is_singlebyte == 0)
 	{
 #if 0
@@ -2638,6 +2639,7 @@
 	  shell_input_line_property[shell_input_line_index - 1] = 1;
 #endif
 	}
+#endif /* HANDLE_MULTIBYTE */
       return ' ';	/* END_ALIAS */
     }
 #endif
diff -ruwN bash-5.2.15/y.tab.c source/y.tab.c
--- bash-5.2.15/y.tab.c	2022-12-13 10:09:02.000000000 -0700
+++ source/y.tab.c	2023-09-09 09:07:14.706070416 -0600
@@ -4936,6 +4936,7 @@
       parser_state |= PST_ENDALIAS;
       /* We need to do this to make sure last_shell_getc_is_singlebyte returns
 	 true, since we are returning a single-byte space. */
+#if defined (HANDLE_MULTIBYTE)
       if (shell_input_line_index == shell_input_line_len && last_shell_getc_is_singlebyte == 0)
 	{
 #if 0
@@ -4949,6 +4950,7 @@
 	  shell_input_line_property[shell_input_line_index - 1] = 1;
 #endif
 	}
+#endif /* HANDLE_MULTIBYTE */
       return ' ';	/* END_ALIAS */
     }
 #endif