From dash  Fri Oct 31 05:10:00 2025
From: Herbert Xu <herbert () gondor ! apana ! org ! au>
Date: Fri, 31 Oct 2025 05:10:00 +0000
To: dash
Subject: [PATCH] options: Call input_init before using stdin_istty
Message-Id: <aQREqBcMzzW1_Blw () gondor ! apana ! org ! au>
X-MARC-Message: https://marc.info/?l=dash&m=176188900609643

j.daubert@posteo.de wrote:
> With dash 0.5.13.1 together with your latest patch I got this:
> 
> $:~> echo date | /bin/sh
> $:\w> Do 30. Okt 12:21:36 CET 2025
> $:\w>
> /bin/sh: 1: Cannot set tty process group (No such process)
> $:~>
> 
> with dash 0.5.12 and bash this works:
> 
> $:~> echo date | /bin/bash
> Do 30. Okt 12:22:52 CET 2025
> $:~>

Oh yes, the input_init optimisation went a bit over the top:

---8<---
Call input_init before using stdin_istty as otherwise it will
always be true.

Reported-by: Juergen Daubert <j.daubert@posteo.de>
Fixes: 6abb589582c6 ("input: Call input_init on first use")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/src/input.c b/src/input.c
index c36d120..c7236d0 100644
--- a/src/input.c
+++ b/src/input.c
@@ -79,8 +79,6 @@ struct parsefile *parsefile = &basepf;	/* current input file */
 int whichprompt;		/* 1 == PS1, 2 == PS2 */
 int stdin_istty = -1;
 
-MKINIT void input_init(void);
-
 STATIC void pushfile(void);
 static void popstring(void);
 static int preadfd(void);
diff --git a/src/input.h b/src/input.h
index 706ac73..59dc5a1 100644
--- a/src/input.h
+++ b/src/input.h
@@ -119,6 +119,7 @@ void unwindfiles(struct parsefile *);
 void popallfiles(void);
 void flush_input(void);
 void reset_input(void);
+void input_init(void);
 
 static inline int input_get_lleft(struct parsefile *pf)
 {
diff --git a/src/options.c b/src/options.c
index c318e0f..c4eedeb 100644
--- a/src/options.c
+++ b/src/options.c
@@ -138,8 +138,11 @@ procargs(char **xargv)
 			sh_error("-c requires an argument");
 		sflag = 1;
 	}
-	if (iflag == 2 && sflag == 1 && stdin_istty && isatty(2))
-		iflag = 1;
+	if (iflag == 2 && sflag == 1) {
+		input_init();
+		if (stdin_istty && isatty(2))
+			iflag = 1;
+	}
 	if (mflag == 2)
 		mflag = iflag;
 	for (i = 0; i < NOPTS; i++)
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt