From e7e70a9f4878848efcbf91572c30d27b8a503984 Mon Sep 17 00:00:00 2001
From: "Jan (janneke) Nieuwenhuizen" <janneke@gnu.org>
Date: Tue, 1 Nov 2022 19:52:53 +0100
Subject: [PATCH] DRAFT lib: Add missing pipe prototype.

* include/unistd.h (pipe: New prototype.
---
 include/unistd.h   | 1 +
 lib/stdio/pclose.c | 2 ++
 lib/stdio/popen.c  | 7 +++----
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/include/unistd.h b/include/unistd.h
index da566fbb..20a20fcb 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -82,6 +82,7 @@ int getpgid (pid_t pid);
 int isatty (int fd);
 int link (char const *old_name, char const *new_name);
 off_t lseek (int fd, off_t offset, int whence);
+int pipe (int filedes[2]);
 ssize_t read (int fd, void *buffer, size_t size);
 ssize_t readlink (char const *file_name, char *buffer, size_t size);
 #if __SBRK_CHAR_PTRDIFF
diff --git a/lib/stdio/pclose.c b/lib/stdio/pclose.c
index 20d91206..72dd6755 100644
--- a/lib/stdio/pclose.c
+++ b/lib/stdio/pclose.c
@@ -26,6 +26,8 @@
 #include <sys/types.h>
 #include <sys/wait.h>
 
+extern int *__ungetc_buf;
+
 int
 pclose (FILE *stream)
 {
diff --git a/lib/stdio/popen.c b/lib/stdio/popen.c
index 71b43204..3afe4e05 100644
--- a/lib/stdio/popen.c
+++ b/lib/stdio/popen.c
@@ -23,6 +23,7 @@
 #include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <signal.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <unistd.h>
@@ -34,8 +35,6 @@
 #define	SHELL_COMMAND_NAME "sh"
 #endif
 
-extern int *__ungetc_buf;
-
 FILE *
 popen (char const *command, char const *mode)
 {
@@ -61,7 +60,7 @@ popen (char const *command, char const *mode)
       // child
       int dup = (*mode == 'w'
                  ? dup2 (pipedes[STDIN], STDIN)
-                 : dup2 (pipedes[STDOUT], STDOUT))
+                 : dup2 (pipedes[STDOUT], STDOUT));
       if (dup < 0)
 	_exit (127);
 
@@ -109,6 +108,6 @@ popen (char const *command, char const *mode)
   // XXX misuse ungetc buffer for PID
   // XXX TODO: make proper FILE struct
   __ungetc_init ();
-  __ungetc_set (filedes, pidchild);
+  __ungetc_set (filedes, pid);
   return stream;
 }