diff --git a/NEWS b/NEWS
index a907545f3..59d1aea9a 100644
--- a/NEWS
+++ b/NEWS
@@ -12,6 +12,11 @@ Any uppercase BUG_* names are modernish shell bug IDs.
   Ref.:	https://github.com/att/ast/issues/425
 	https://github.com/att/ast/pull/442
 
+- Fix BUG_PUTIOERR: Output builtins now correctly detect and report
+  input/output errors. This allows scripts to check for a nonzero exit
+  status on the 'print', 'printf' and 'echo' builtins and prevent possible
+  infinite loops if SIGPIPE is ignored.
+
 2020-05-13:
 
 - Fix BUG_CASELIT: an undocumented 'case' pattern matching misbehaviour that
diff --git a/TODO b/TODO
index ae9327cb3..c92aed97b 100644
--- a/TODO
+++ b/TODO
@@ -92,10 +92,5 @@ https://github.com/modernish/modernish/tree/0.16/lib/modernish/cap/
   example, "$*" joins positional parameters on the first byte of IFS instead
   of the first character.
 
-- BUG_PUTIOERR: Shell builtins that output strings (echo, printf, ksh/zsh
-  print), and thus also modernish put and putln, do not check for I/O errors
-  on output. This means a script cannot check for them, and a script process
-  in a pipe can get stuck in an infinite loop if SIGPIPE is ignored.
-
 - BUG_TESTERR1A: test/[ exits with a non-error false status (1) if an
   invalid argument is given to an operator.
diff --git a/src/cmd/ksh93/bltins/print.c b/src/cmd/ksh93/bltins/print.c
index ee6f2fdf0..6d2f30203 100644
--- a/src/cmd/ksh93/bltins/print.c
+++ b/src/cmd/ksh93/bltins/print.c
@@ -336,9 +336,11 @@ skip2:
 		 * https://github.com/att/ast/issues/425
 		 */
 		if(!sflag && sffileno(outfile)!=sffileno(sfstderr))
-			sfsync(outfile);
+			if (sfsync(outfile) < 0)
+				exitval = 1;
 		sfpool(sfstderr,pool,SF_WRITE);
-		exitval = pdata.err;
+		if (pdata.err)
+			exitval = 1;
 	}
 	else if(vflag)
 	{
@@ -353,7 +355,10 @@ skip2:
 	{
 		/* echo style print */
 		if(nflag && !argv[0])
-			sfsync((Sfio_t*)0);
+		{
+			if (sfsync((Sfio_t*)0) < 0)
+				exitval = 1;
+		}
 		else if(sh_echolist(shp,outfile,rflag,argv) && !nflag)
 			sfputc(outfile,'\n');
 	}
@@ -365,8 +370,11 @@ skip2:
 	else if(n&SF_SHARE)
 	{
 		sfset(outfile,SF_SHARE|SF_PUBLIC,1);
-		sfsync(outfile);
+		if (sfsync(outfile) < 0)
+			exitval = 1;
 	}
+	if (exitval)
+		errormsg(SH_DICT, 2, e_io);
 	return(exitval);
 }
 
diff --git a/src/cmd/ksh93/data/msg.c b/src/cmd/ksh93/data/msg.c
index a4eead98f..d56e2d32a 100644
--- a/src/cmd/ksh93/data/msg.c
+++ b/src/cmd/ksh93/data/msg.c
@@ -89,6 +89,7 @@ const char e_access[]		= "permission denied";
 const char e_direct[]		= "bad directory";
 const char e_file[]		= "%s: bad file unit number";
 const char e_redirect[]		= "redirection failed";
+const char e_io[]		= "I/O error";
 const char e_trap[]		= "%s: bad trap";
 const char e_readonly[]		= "%s: is read only";
 const char e_badfield[]		= "%d: negative field size";
diff --git a/src/cmd/ksh93/include/io.h b/src/cmd/ksh93/include/io.h
index f82c5ca10..5836d0dc0 100644
--- a/src/cmd/ksh93/include/io.h
+++ b/src/cmd/ksh93/include/io.h
@@ -97,6 +97,7 @@ extern const char	e_tmpcreate[];
 extern const char	e_exists[];
 extern const char	e_file[];
 extern const char	e_redirect[];
+extern const char	e_io[];
 extern const char	e_formspec[];
 extern const char	e_badregexp[];
 extern const char	e_open[];
diff --git a/src/cmd/ksh93/tests/basic.sh b/src/cmd/ksh93/tests/basic.sh
index 4613baee2..f8b4794e7 100755
--- a/src/cmd/ksh93/tests/basic.sh
+++ b/src/cmd/ksh93/tests/basic.sh
@@ -431,7 +431,7 @@ done | while read sec; do ( $sleep $sec; $sleep $sec) done
 s=SECONDS
 set -o pipefail
 for ((i=0; i < 30; i++))
-do	print hello
+do	print hello 2>/dev/null
 	sleep .1
 done |  $sleep 1
 (( (SECONDS-s) < 2 )) || err_exit 'early termination not causing broken pipe'
@@ -470,7 +470,7 @@ bintrue=$(whence -p true)
 set -o pipefail
 float start=$SECONDS end 
 for ((i=0; i < 2; i++))
-do	print foo
+do	print foo 2>/dev/null
 	sleep 1.5
 done | { read; $bintrue; end=$SECONDS ;}
 (( (SECONDS-start) < 1 )) && err_exit "pipefail not waiting for pipe to finish"
diff --git a/src/cmd/ksh93/tests/builtins.sh b/src/cmd/ksh93/tests/builtins.sh
index 3b191546c..4ad461f4a 100755
--- a/src/cmd/ksh93/tests/builtins.sh
+++ b/src/cmd/ksh93/tests/builtins.sh
@@ -639,4 +639,26 @@ read baz <<< 'foo\\\\bar'
 : ~root
 [[ $(builtin) == *.sh.tilde* ]] &&  err_exit 'builtin contains .sh.tilde'
 
+# ======
+# Check that I/O errors are detected <https://github.com/att/ast/issues/1093>
+actual=$(
+    {
+        (
+            trap "" PIPE
+            for ((i = SECONDS + 1; SECONDS < i; )); do
+                print hi || {
+                    print $? >&2
+                    exit
+                }
+            done
+        ) | true
+    } 2>&1
+)
+expect=$': print: I/O error\n1'
+if [[ $actual != *"$expect" ]]
+then
+    err_exit "I/O error not detected (expected '$expect', got '$actual')"
+fi
+
+# ======
 exit $((Errors<125?Errors:125))
diff --git a/src/cmd/ksh93/tests/coprocess.sh b/src/cmd/ksh93/tests/coprocess.sh
index 2b0b50d0e..93a47e8dd 100755
--- a/src/cmd/ksh93/tests/coprocess.sh
+++ b/src/cmd/ksh93/tests/coprocess.sh
@@ -266,7 +266,7 @@ _COSHELL_msgfd=5
 function cop
 {
 	read
-	print ok
+	print ok 2>/dev/null
 }
 
 exp=ok
@@ -342,7 +342,7 @@ wait
 function cop
 {
         read
-        print ok
+        print ok 2>/dev/null
 }
 exp=ok
 cop |&