diff --git a/include/ntux/ntux.h b/include/ntux/ntux.h
index 07c735b..d43e8ad 100644
--- a/include/ntux/ntux.h
+++ b/include/ntux/ntux.h
@@ -64,6 +64,15 @@ struct ntux_source_version {
 	const char *	commit;
 };
 
+struct ntux_fd_ctx {
+	int		fdin;
+	int		fdout;
+	int		fderr;
+	int		fdlog;
+	int		fdcwd;
+	int		fddst;
+};
+
 struct ntux_error_info {
 	const struct ntux_driver_ctx *	edctx;
 	const struct ntux_unit_ctx *	euctx;
@@ -107,17 +116,21 @@ struct ntux_unit_ctx {
 
 /* driver api */
 ntux_api int  ntux_get_driver_ctx       (char **, char **, uint32_t,
+                                         const struct ntux_fd_ctx *,
                                          struct ntux_driver_ctx **);
 
 ntux_api void ntux_free_driver_ctx      (struct ntux_driver_ctx *);
 
+ntux_api int  ntux_get_driver_fdctx     (const struct ntux_driver_ctx *, struct ntux_fd_ctx *);
+ntux_api int  ntux_set_driver_fdctx     (struct ntux_driver_ctx *, const struct ntux_fd_ctx *);
+
 /* cmd api */
 ntux_api int  ntux_cmd_stat             (const struct ntux_driver_ctx *, const char *);
 ntux_api int  ntux_cmd_spawn            (const struct ntux_driver_ctx *);
 ntux_api int  ntux_cmd_strace           (const struct ntux_driver_ctx *);
 
 /* utility api */
-ntux_api int  ntux_main                 (int, char **, char **);
+ntux_api int  ntux_main                 (int, char **, char **, const struct ntux_fd_ctx *);
 
 /* error trace api */
 ntux_api int  ntux_output_error_vector  (const struct ntux_driver_ctx *);
diff --git a/src/driver/ntux_amain.c b/src/driver/ntux_amain.c
index b6719ff..22a1403 100644
--- a/src/driver/ntux_amain.c
+++ b/src/driver/ntux_amain.c
@@ -8,6 +8,7 @@
 #include <unistd.h>
 
 #include <ntux/ntux.h>
+#include "ntux_dprintf_impl.h"
 #include "ntux_driver_impl.h"
 #include "ntux_nolibc_impl.h"
 
@@ -32,16 +33,16 @@ static const char * const ntux_ver_plain[6] = {
 		"",""
 };
 
-static ssize_t ntux_version(struct ntux_driver_ctx * dctx)
+static ssize_t ntux_version(struct ntux_driver_ctx * dctx, int fdout)
 {
 	const struct ntux_source_version * verinfo;
 	const char * const * verclr;
 
 	verinfo = ntux_source_version();
-	verclr  = isatty(STDOUT_FILENO) ? ntux_ver_color : ntux_ver_plain;
+	verclr  = isatty(fdout) ? ntux_ver_color : ntux_ver_plain;
 
 	return ntux_dprintf(
-			STDOUT_FILENO,vermsg,
+			fdout,vermsg,
 			verclr[0],dctx->program,verclr[1],
 			verclr[2],verinfo->major,verinfo->minor,
 			verinfo->revision,verclr[3],
@@ -63,19 +64,24 @@ static int ntux_exit(struct ntux_driver_ctx * dctx, int ret)
 	return ret;
 }
 
-int ntux_main(int argc, char ** argv, char ** envp)
+int ntux_main(int argc, char ** argv, char ** envp, const struct ntux_fd_ctx * fdctx)
 {
 	int				ret;
+	int				fdout;
+	uint64_t			flags;
 	struct ntux_driver_ctx *	dctx;
 	const char **			unit;
 
-	if ((ret = ntux_get_driver_ctx(argv,envp,NTUX_DRIVER_FLAGS,&dctx)))
+	flags = NTUX_DRIVER_FLAGS;
+	fdout = fdctx ? fdctx->fdout : STDOUT_FILENO;
+
+	if ((ret = ntux_get_driver_ctx(argv,envp,flags,fdctx,&dctx)))
 		return (ret == NTUX_USAGE)
 			? !--argc
 			: NTUX_ERROR;
 
 	if (dctx->cctx->drvflags & NTUX_DRIVER_VERSION)
-		if ((ntux_version(dctx)) < 0)
+		if ((ntux_version(dctx,fdout)) < 0)
 			return ntux_exit(dctx,NTUX_ERROR);
 
 	if (dctx->cctx->cmd == NTUX_CMD_SPAWN)
diff --git a/src/driver/ntux_driver_ctx.c b/src/driver/ntux_driver_ctx.c
index 954b2db..243a729 100644
--- a/src/driver/ntux_driver_ctx.c
+++ b/src/driver/ntux_driver_ctx.c
@@ -6,6 +6,7 @@
 
 #include <ntapi/ntapi.h>
 #include <psxscl/psxscl.h>
+#include <psxabi/sys_fcntl.h>
 #include <stdint.h>
 
 #include <ntux/ntux.h>
@@ -76,6 +77,7 @@ static uint32_t ntux_argv_flags(uint32_t flags)
 }
 
 static int ntux_driver_usage(
+	int				fdout,
 	const char *			program,
 	const char *			arg,
 	const struct argv_option **	optv,
@@ -107,7 +109,7 @@ static int ntux_driver_usage(
 		"Options%s%s%s:\n",
 		program,program,cmdarg[0],cmdname,cmdarg[1]);
 
-	argv_usage(STDOUT_FILENO,header,optv,arg);
+	argv_usage(fdout,header,optv,arg);
 	argv_free(meta);
 
 	return NTUX_USAGE;
@@ -115,6 +117,7 @@ static int ntux_driver_usage(
 
 static struct ntux_driver_ctx_impl * ntux_driver_ctx_alloc(
 	struct argv_meta *		meta,
+	const struct ntux_fd_ctx *	fdctx,
 	const struct ntux_common_ctx *	cctx,
 	size_t				nunits)
 {
@@ -137,8 +140,8 @@ static struct ntux_driver_ctx_impl * ntux_driver_ctx_alloc(
 	ictx->ctx.errinfp  = &ictx->ctx.erriptr[0];
 	ictx->ctx.erricap  = &ictx->ctx.erriptr[--elements];
 
-	if (cctx)
-		memcpy(&ictx->ctx.cctx,cctx,sizeof(*cctx));
+	memcpy(&ictx->ctx.fdctx,fdctx,sizeof(*fdctx));
+	memcpy(&ictx->ctx.cctx,cctx,sizeof(*cctx));
 
 	for (entry=meta->entries,units=ictx->units; entry->fopt || entry->arg; entry++)
 		if (!entry->fopt)
@@ -155,6 +158,7 @@ static int ntux_cctx_update(
 	const struct argv_option **	optv,
 	struct argv_meta *		meta,
 	uint32_t			flags,
+	const struct ntux_fd_ctx *	fdctx,
 	struct ntux_common_ctx *	cctx,
 	size_t *			nunits)
 {
@@ -167,6 +171,7 @@ static int ntux_cctx_update(
 				case TAG_HELP:
 					if (flags & NTUX_DRIVER_VERBOSITY_USAGE)
 						return ntux_driver_usage(
+							fdctx->fdout,
 							program,entry->arg,
 							optv,0,cctx->cmd);
 
@@ -177,6 +182,7 @@ static int ntux_cctx_update(
 				case TAG_CMD:
 					if (*nunits)
 						return ntux_driver_usage(
+							fdctx->fderr,
 							program,entry->arg,
 							optv,0,cctx->cmd);
 
@@ -243,6 +249,7 @@ int ntux_get_driver_ctx(
 	char **				argv,
 	char **				envp,
 	uint32_t			flags,
+	const struct ntux_fd_ctx *	fdctx,
 	struct ntux_driver_ctx **	pctx)
 {
 	struct ntux_driver_ctx_impl *	ictx;
@@ -264,6 +271,19 @@ int ntux_get_driver_ctx(
 	if (ntux_init())
 		return -1;
 
+	/* fdctx */
+	if (!fdctx) {
+		fdctx = &(const struct ntux_fd_ctx) {
+			.fdin  = STDIN_FILENO,
+			.fdout = STDOUT_FILENO,
+			.fderr = STDERR_FILENO,
+			.fdlog = (-1),
+			.fdcwd = AT_FDCWD,
+			.fddst = AT_FDCWD,
+		};
+	}
+
+	/* cctx */
 	memset(&cctx,0,sizeof(cctx));
 
 	nunits	      = 0;
@@ -276,7 +296,10 @@ int ntux_get_driver_ctx(
 	argv_optv_init(ntux_cmd_options[cctx.cmd],optv);
 
 	if (!argv[1] && (flags & NTUX_DRIVER_VERBOSITY_USAGE))
-		return ntux_driver_usage(program,0,optv,0,cctx.cmd);
+		return ntux_driver_usage(
+			fdctx->fderr,
+			program,0,
+			optv,0,cctx.cmd);
 
 	/* initial argv scan: ... --cmd=xxx ... */
 	for (parg=argv, cmdargv=0; *parg && !cmdargv; parg++) {
@@ -296,10 +319,12 @@ int ntux_get_driver_ctx(
 		if (!(meta = argv_get(
 				argv,optv,
 				ntux_argv_flags(flags),
-				STDERR_FILENO)))
+				fdctx->fderr)))
 			return -1;
 
-		if (ntux_cctx_update(program,optv,meta,flags,&cctx,&nunits)) {
+		if (ntux_cctx_update(
+				program,optv,meta,flags,
+				fdctx,&cctx,&nunits)) {
 			argv_free(meta);
 			return -1;
 		}
@@ -325,12 +350,15 @@ int ntux_get_driver_ctx(
 				argv_get(
 					argv,optv,
 					ntux_argv_flags(flags),
-					STDERR_FILENO);
+					fdctx->fderr);
 			return -1;
 		}
 
 		if (!ctx.unitidx && (flags & NTUX_DRIVER_VERBOSITY_USAGE))
-			ntux_driver_usage(program,0,optv,0,cctx.cmd);
+			ntux_driver_usage(
+				fdctx->fderr,
+				program,0,
+				optv,0,cctx.cmd);
 
 		if (!ctx.unitidx)
 			return NTUX_ERROR;
@@ -344,10 +372,12 @@ int ntux_get_driver_ctx(
 	if (!(meta = argv_get(
 			argv,optv,
 			ntux_argv_flags(flags),
-			STDERR_FILENO)))
+			fdctx->fderr)))
 		return -1;
 
-	if (ntux_cctx_update(program,optv,meta,flags,&cctx,&nunits)) {
+	if (ntux_cctx_update(
+			program,optv,meta,flags,
+			fdctx,&cctx,&nunits)) {
 		argv_free(meta);
 		return -1;
 	}
@@ -362,9 +392,13 @@ int ntux_get_driver_ctx(
 
 	/* finalize */
 	if (nunits && !cctx.cmd)
-		return ntux_driver_usage(program,0,optv,meta,NTUX_CMD_DEFAULT);
+		return ntux_driver_usage(
+			fdctx->fderr,
+			program,0,
+			optv,meta,
+			NTUX_CMD_DEFAULT);
 
-	if (!(ictx = ntux_driver_ctx_alloc(meta,&cctx,nunits)))
+	if (!(ictx = ntux_driver_ctx_alloc(meta,fdctx,&cctx,nunits)))
 		return ntux_get_driver_ctx_fail(meta);
 
 	ictx->ctx.program = program;
@@ -397,3 +431,39 @@ const struct ntux_source_version * ntux_source_version(void)
 {
 	return &ntux_src_version;
 }
+
+int ntux_get_driver_fdctx(
+	const struct ntux_driver_ctx *	dctx,
+	struct ntux_fd_ctx *		fdctx)
+{
+	struct ntux_driver_ctx_impl *	ictx;
+
+	ictx = ntux_get_driver_ictx(dctx);
+
+	fdctx->fdin  = ictx->fdctx.fdin;
+	fdctx->fdout = ictx->fdctx.fdout;
+	fdctx->fderr = ictx->fdctx.fderr;
+	fdctx->fdlog = ictx->fdctx.fdlog;
+	fdctx->fdcwd = ictx->fdctx.fdcwd;
+	fdctx->fddst = ictx->fdctx.fddst;
+
+	return 0;
+}
+
+int ntux_set_driver_fdctx(
+	struct ntux_driver_ctx *	dctx,
+	const struct ntux_fd_ctx *	fdctx)
+{
+	struct ntux_driver_ctx_impl *	ictx;
+
+	ictx = ntux_get_driver_ictx(dctx);
+
+	ictx->fdctx.fdin  = fdctx->fdin;
+	ictx->fdctx.fdout = fdctx->fdout;
+	ictx->fdctx.fderr = fdctx->fderr;
+	ictx->fdctx.fdlog = fdctx->fdlog;
+	ictx->fdctx.fdcwd = fdctx->fdcwd;
+	ictx->fdctx.fddst = fdctx->fddst;
+
+	return 0;
+}
diff --git a/src/internal/ntux_driver_impl.h b/src/internal/ntux_driver_impl.h
index 32e3d1f..e55fdb6 100644
--- a/src/internal/ntux_driver_impl.h
+++ b/src/internal/ntux_driver_impl.h
@@ -30,6 +30,7 @@ enum app_tags {
 struct ntux_driver_ctx_impl {
 	struct ntux_common_ctx      cctx;
 	struct ntux_driver_ctx      ctx;
+	struct ntux_fd_ctx          fdctx;
 	struct __psx_context        xctx;
 	const struct ntux_unit_ctx *euctx;
 	const char *                eunit;
@@ -66,4 +67,46 @@ static inline void ntux_driver_set_ectx(
 	ictx->eunit = unit;
 }
 
+static inline int ntux_driver_fdin(const struct ntux_driver_ctx * dctx)
+{
+	struct ntux_fd_ctx fdctx;
+	ntux_get_driver_fdctx(dctx,&fdctx);
+	return fdctx.fdin;
+}
+
+static inline int ntux_driver_fdout(const struct ntux_driver_ctx * dctx)
+{
+	struct ntux_fd_ctx fdctx;
+	ntux_get_driver_fdctx(dctx,&fdctx);
+	return fdctx.fdout;
+}
+
+static inline int ntux_driver_fderr(const struct ntux_driver_ctx * dctx)
+{
+	struct ntux_fd_ctx fdctx;
+	ntux_get_driver_fdctx(dctx,&fdctx);
+	return fdctx.fderr;
+}
+
+static inline int ntux_driver_fdlog(const struct ntux_driver_ctx * dctx)
+{
+	struct ntux_fd_ctx fdctx;
+	ntux_get_driver_fdctx(dctx,&fdctx);
+	return fdctx.fdlog;
+}
+
+static inline int ntux_driver_fdcwd(const struct ntux_driver_ctx * dctx)
+{
+	struct ntux_fd_ctx fdctx;
+	ntux_get_driver_fdctx(dctx,&fdctx);
+	return fdctx.fdcwd;
+}
+
+static inline int ntux_driver_fddst(const struct ntux_driver_ctx * dctx)
+{
+	struct ntux_fd_ctx fdctx;
+	ntux_get_driver_fdctx(dctx,&fdctx);
+	return fdctx.fddst;
+}
+
 #endif
diff --git a/src/ntux.c b/src/ntux.c
index 890fbc0..7629d7e 100644
--- a/src/ntux.c
+++ b/src/ntux.c
@@ -26,7 +26,7 @@ int ntux_entry_routine(
 
 	/* invoke main */
 	__sys_exit_group(
-		ntux_main(argc,argv,envp));
+		ntux_main(argc,argv,envp,0));
 
 	return NT_STATUS_INTERNAL_ERROR;
 }