* cygheap.h (class cygheap_fdenum): New class to enumerate used

	fhandlers.
	* dtable.h (class dtable): Add cygheap_fdenum as friend class.
	* fhandler.h (fhandler_base::get_proc_fd_name): New virtual method
	to return a name for /proc/<pid>/fd.
	(fhandler_socket::get_proc_fd_name): Ditto.
	(fhandler_pipe::get_proc_fd_name): Ditto.
	(fhandler_virtual::opendir): Make virtual method.
	(fhandler_process::opendir): New method.
	* fhandler.cc (fhandler_base::get_proc_fd_name): New method.
	* fhandler_process.cc: Include ctype.h.
	(PROCESS_FD): Define.
	(process_listing): Add "fd".
	(fhandler_process::exists): Fix comment.  Return 1 in case of "fd"
	directory. Handle files below "fd".
	(fhandler_process::fstat): Drop "self" handling.  Set correct link
	count for directories.
	(fhandler_process::opendir): New method to handle "fd" directory.
	(fhandler_process::readdir): Add "fd" handling.
	(fhandler_process::open): Drop "self" handling.
	(fhandler_process::fill_filebuf): Ditto.  Add "fd" handling.  Fix
	"maps" output string.
	* fhandler_registry.cc (fhandler_registry::fstat): Set correct link
	count for directories.
	* fhandler_socket.cc (fhandler_socket::get_proc_fd_name): New method.
	* path.cc (symlink_info::set): Fix thinko.
	* pinfo.cc (_pinfo::commune_recv): Rename pathbuf to path throughout.
	Drop local path variable in PICOM_FIFO case.  Fix debug output.
	Close handles as early as possible. Add PICOM_FDS and PICOM_FD
	handling.
	(_pinfo::commune_send): Add PICOM_FDS and PICOM_FD handling.
	(_pinfo::fd): New method.
	(_pinfo::fds): New method.
	* pinfo.h (enum picom): Add PICOM_FDS and PICOM_FD.
	(_pinfo::fd): Declare.
	(_pinfo::fds): Declare.
	* pipe.cc (fhandler_pipe::get_proc_fd_name): New method.

12 files changed, 307 insertions, 58 deletions

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index ff4b3bd59..0f390e4cc 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,43 @@
+2005-01-31  Corinna Vinschen  <corinna@vinschen.de>
+
+	* cygheap.h (class cygheap_fdenum): New class to enumerate used
+	fhandlers.
+	* dtable.h (class dtable): Add cygheap_fdenum as friend class.
+	* fhandler.h (fhandler_base::get_proc_fd_name): New virtual method
+	to return a name for /proc/<pid>/fd.
+	(fhandler_socket::get_proc_fd_name): Ditto.
+	(fhandler_pipe::get_proc_fd_name): Ditto.
+	(fhandler_virtual::opendir): Make virtual method.
+	(fhandler_process::opendir): New method.
+	* fhandler.cc (fhandler_base::get_proc_fd_name): New method.
+	* fhandler_process.cc: Include ctype.h.
+	(PROCESS_FD): Define.
+	(process_listing): Add "fd".
+	(fhandler_process::exists): Fix comment.  Return 1 in case of "fd"
+	directory. Handle files below "fd".
+	(fhandler_process::fstat): Drop "self" handling.  Set correct link
+	count for directories.
+	(fhandler_process::opendir): New method to handle "fd" directory.
+	(fhandler_process::readdir): Add "fd" handling.
+	(fhandler_process::open): Drop "self" handling.
+	(fhandler_process::fill_filebuf): Ditto.  Add "fd" handling.  Fix
+	"maps" output string.
+	* fhandler_registry.cc (fhandler_registry::fstat): Set correct link
+	count for directories.
+	* fhandler_socket.cc (fhandler_socket::get_proc_fd_name): New method.
+	* path.cc (symlink_info::set): Fix thinko.
+	* pinfo.cc (_pinfo::commune_recv): Rename pathbuf to path throughout.
+	Drop local path variable in PICOM_FIFO case.  Fix debug output.
+	Close handles as early as possible. Add PICOM_FDS and PICOM_FD
+	handling.
+	(_pinfo::commune_send): Add PICOM_FDS and PICOM_FD handling.
+	(_pinfo::fd): New method.
+	(_pinfo::fds): New method.
+	* pinfo.h (enum picom): Add PICOM_FDS and PICOM_FD.
+	(_pinfo::fd): Declare.
+	(_pinfo::fds): Declare.
+	* pipe.cc (fhandler_pipe::get_proc_fd_name): New method.
+
 2005-01-29  Corinna Vinschen  <corinna@vinschen.de>
 
 	* smallprint.c (rn): Change uval to unsigned long long to fix 64 bit
diff --git a/winsup/cygwin/cygheap.h b/winsup/cygwin/cygheap.h
index d3baae329..43723244d 100644
--- a/winsup/cygwin/cygheap.h
+++ b/winsup/cygwin/cygheap.h
@@ -384,6 +384,29 @@ class cygheap_fdget : public cygheap_fdmanip
   }
 };
 
+class cygheap_fdenum : public cygheap_fdmanip
+{
+  int start_fd;
+ public:
+  cygheap_fdenum (int start_fd = -1, bool lockit = false)
+  {
+    if (lockit)
+      cygheap->fdtab.lock ();
+    this->start_fd = fd = start_fd < 0 ? -1 : start_fd;
+  }
+  int next ()
+  {
+    while (++fd < (int) cygheap->fdtab.size)
+      if (*(fh = cygheap->fdtab + fd) != NULL)
+        return fd;
+    return -1;
+  }
+  void rewind ()
+  {
+    fd = start_fd;
+  }
+};
+
 class child_info;
 void *__stdcall cygheap_setup_for_child (child_info *ci, bool dup_later) __attribute__ ((regparm(2)));
 void __stdcall cygheap_setup_for_child_cleanup (void *, child_info *, bool) __attribute__ ((regparm(3)));
diff --git a/winsup/cygwin/dtable.h b/winsup/cygwin/dtable.h
index 0c6153aae..f7ae7740f 100644
--- a/winsup/cygwin/dtable.h
+++ b/winsup/cygwin/dtable.h
@@ -88,6 +88,7 @@ public:
   friend class cygheap_fdmanip;
   friend class cygheap_fdget;
   friend class cygheap_fdnew;
+  friend class cygheap_fdenum;
 };
 
 fhandler_base *build_fh_dev (const device&, const char * = NULL);
diff --git a/winsup/cygwin/fhandler.cc b/winsup/cygwin/fhandler.cc
index 4438a5d2c..ba539a33e 100644
--- a/winsup/cygwin/fhandler.cc
+++ b/winsup/cygwin/fhandler.cc
@@ -154,6 +154,16 @@ fhandler_base::set_name (path_conv &in_pc)
   pc.set_normalized_path (in_pc.normalized_path, false);
 }
 
+char *fhandler_base::get_proc_fd_name (char *buf)
+{
+  if (get_name ())
+    return strcpy (buf, get_name ());
+  if (dev ().name)
+    return strcpy (buf, dev ().name);
+  __small_sprintf (buf, "device:[%d:%d]", get_major (), get_minor ());
+  return buf;
+}
+
 /* Detect if we are sitting at EOF for conditions where Windows
    returns an error but UNIX doesn't.  */
 static int __stdcall
diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index f1041c68c..3879e067e 100644
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -218,6 +218,8 @@ class fhandler_base
   const char *get_name () const { return pc.normalized_path; }
   const char *get_win32_name () { return pc.get_win32 (); }
     __ino64_t get_namehash () { return namehash ?: namehash = hash_path_name (0, get_win32_name ()); }
+  /* Returns name used for /proc/<pid>/fd in buf. */
+  virtual char *get_proc_fd_name (char *buf);
 
   virtual void hclose (HANDLE h) {CloseHandle (h);}
   virtual void set_no_inheritance (HANDLE &h, int not_inheriting);
@@ -398,6 +400,7 @@ class fhandler_socket: public fhandler_base
   void fixup_after_fork (HANDLE);
   void fixup_after_exec ();
   bool need_fixup_before () const {return true;}
+  char *get_proc_fd_name (char *buf);
 
   select_record *select_read (select_record *s);
   select_record *select_write (select_record *s);
@@ -432,6 +435,7 @@ public:
   select_record *select_read (select_record *s);
   select_record *select_write (select_record *s);
   select_record *select_except (select_record *s);
+  char *get_proc_fd_name (char *buf);
   void set_close_on_exec (bool val);
   void __stdcall read (void *ptr, size_t& len) __attribute__ ((regparm (3)));
   int close ();
@@ -1105,7 +1109,7 @@ class fhandler_virtual : public fhandler_base
   virtual ~fhandler_virtual();
 
   virtual int exists();
-  DIR *opendir ();
+  virtual DIR *opendir ();
   _off64_t telldir (DIR *);
   void seekdir (DIR *, _off64_t);
   void rewinddir (DIR *);
@@ -1164,6 +1168,7 @@ class fhandler_process: public fhandler_proc
  public:
   fhandler_process ();
   int exists();
+  DIR *opendir ();
   struct dirent *readdir (DIR *);
   int open (int flags, mode_t mode = 0);
   int __stdcall fstat (struct __stat64 *buf) __attribute__ ((regparm (2)));
diff --git a/winsup/cygwin/fhandler_process.cc b/winsup/cygwin/fhandler_process.cc
index 0115a4eb2..fda7e52a1 100644
--- a/winsup/cygwin/fhandler_process.cc
+++ b/winsup/cygwin/fhandler_process.cc
@@ -25,6 +25,7 @@ details. */
 #include <sys/param.h>
 #include <assert.h>
 #include <sys/sysmacros.h>
+#include <ctype.h>
 #include <psapi.h>
 
 #define _COMPILING_NEWLIB
@@ -43,10 +44,11 @@ static const int PROCESS_STAT = 11;
 static const int PROCESS_STATM = 12;
 static const int PROCESS_CMDLINE = 13;
 static const int PROCESS_MAPS = 14;
+static const int PROCESS_FD = 15;
 /* Keep symlinks always the last entries. */
-static const int PROCESS_ROOT = 15;
-static const int PROCESS_EXE = 16;
-static const int PROCESS_CWD = 17;
+static const int PROCESS_ROOT = 16;
+static const int PROCESS_EXE = 17;
+static const int PROCESS_CWD = 18;
 
 /* The position of "root" defines the beginning of symlik entries. */
 #define is_symlink(nr) ((nr) >= PROCESS_ROOT)
@@ -68,6 +70,7 @@ static const char * const process_listing[] =
   "statm",
   "cmdline",
   "maps",
+  "fd",
   /* Keep symlinks always the last entries. */
   "root",
   "exe",
@@ -89,7 +92,7 @@ static bool get_mem_values (DWORD dwProcessId, unsigned long *vmsize,
 			    unsigned long *vmshare);
 
 /* Returns 0 if path doesn't exist, >0 if path is a directory,
- * <0 if path is a file.
+ * -1 if path is a file, -2 if path is a symlink.
  */
 int
 fhandler_process::exists ()
@@ -106,8 +109,14 @@ fhandler_process::exists ()
     if (pathmatch (path + 1, process_listing[i]))
       {
 	fileid = i;
-	return is_symlink (i) ? -2 : -1;
+	return is_symlink (i) ? -2 : (i == PROCESS_FD) ? 1 : -1;
       }
+  if (pathnmatch (strchr (path, '/') + 1, "fd/", 3))
+    {
+      fileid = PROCESS_FD;
+      if (fill_filebuf ())
+        return -2;
+    }
   return 0;
 }
 
@@ -123,10 +132,7 @@ fhandler_process::fstat (struct __stat64 *buf)
   int file_type = exists ();
   (void) fhandler_base::fstat (buf);
   path += proc_len + 1;
-  if (path_prefix_p ("self", path, 4))
-    pid = getpid ();
-  else
-    pid = atoi (path);
+  pid = atoi (path);
   pinfo p (pid);
   if (!p)
     {
@@ -142,8 +148,6 @@ fhandler_process::fstat (struct __stat64 *buf)
       set_errno (ENOENT);
       return -1;
     case 1:
-      buf->st_mode |= S_IFDIR | S_IXUSR | S_IXGRP | S_IXOTH;
-      return 0;
     case 2:
       buf->st_ctime = buf->st_mtime = p->start_time;
       buf->st_ctim.tv_nsec = buf->st_mtim.tv_nsec = 0;
@@ -151,7 +155,10 @@ fhandler_process::fstat (struct __stat64 *buf)
       buf->st_uid = p->uid;
       buf->st_gid = p->gid;
       buf->st_mode |= S_IFDIR | S_IXUSR | S_IXGRP | S_IXOTH;
-      buf->st_nlink = PROCESS_LINK_COUNT;
+      if (file_type == 1)
+	buf->st_nlink = 2;
+      else
+	buf->st_nlink = 3;
       return 0;
     case -2:
       buf->st_uid = p->uid;
@@ -167,14 +174,38 @@ fhandler_process::fstat (struct __stat64 *buf)
     }
 }
 
+DIR *
+fhandler_process::opendir ()
+{
+  DIR *dir = fhandler_virtual::opendir ();
+  if (dir && fileid == PROCESS_FD)
+    fill_filebuf ();
+  return dir;
+}
+
 struct dirent *
 fhandler_process::readdir (DIR * dir)
 {
-  if (dir->__d_position >= PROCESS_LINK_COUNT)
+  if (fileid == PROCESS_FD)
+    {
+      if (dir->__d_position >= 2 + filesize / sizeof (int))
+        return NULL;
+    }
+  else if (dir->__d_position >= PROCESS_LINK_COUNT)
     return NULL;
-  strcpy (dir->__d_dirent->d_name, process_listing[dir->__d_position++]);
-  syscall_printf ("%p = readdir (%p) (%s)", &dir->__d_dirent, dir,
-		  dir->__d_dirent->d_name);
+  if (fileid == PROCESS_FD && dir->__d_position > 1)
+    {
+      int *p = (int *) filebuf;
+      __small_sprintf (dir->__d_dirent->d_name, "%d", p[dir->__d_position++ - 2]);
+      syscall_printf ("%p = readdir (%p) (%s)", &dir->__d_dirent, dir,
+		      dir->__d_dirent->d_name);
+    }
+  else
+    {
+      strcpy (dir->__d_dirent->d_name, process_listing[dir->__d_position++]);
+      syscall_printf ("%p = readdir (%p) (%s)", &dir->__d_dirent, dir,
+		      dir->__d_dirent->d_name);
+    }
   return dir->__d_dirent;
 }
 
@@ -191,10 +222,7 @@ fhandler_process::open (int flags, mode_t mode)
 
   const char *path;
   path = get_name () + proc_len + 1;
-  if (path_prefix_p ("self", path, 4))
-    pid = getpid ();
-  else
-    pid = atoi (path);
+  pid = atoi (path);
   while (*path != 0 && !isdirsep (*path))
     path++;
 
@@ -272,15 +300,11 @@ out:
 bool
 fhandler_process::fill_filebuf ()
 {
+  const char *path;
+  path = get_name () + proc_len + 1;
   if (!pid)
-    {
-      const char *path;
-      path = get_name () + proc_len + 1;
-      if (path_prefix_p ("self", path, 4))
-	pid = getpid ();
-      else
-	pid = atoi (path);
-    }
+    pid = atoi (path);
+
   pinfo p (pid);
 
   if (!p)
@@ -291,6 +315,36 @@ fhandler_process::fill_filebuf ()
 
   switch (fileid)
     {
+    case PROCESS_FD:
+      {
+	size_t fs; 
+	char *fdp = strrchr (path, '/');
+	if (!fdp || *++fdp == 'f') /* The "fd" directory itself. */
+	  {
+	    if (filebuf)
+	      free (filebuf);
+	    filebuf = p->fds (fs);
+	  }
+	else
+	  {
+	    if (filebuf)
+	      free (filebuf);
+	    int fd = atoi (fdp);
+	    if (fd < 0 || (fd == 0 && !isdigit (*fdp)))
+	      {
+		set_errno (ENOENT);
+		return false;
+	      }
+	    filebuf = p->fd (fd, fs);
+	    if (!filebuf || !*filebuf)
+	      {
+		filebuf = strdup ("<disconnected>");
+		fs = strlen (filebuf) + 1;
+	      }
+	  }
+	filesize = fs;
+	break;
+      }
     case PROCESS_UID:
     case PROCESS_GID:
     case PROCESS_PGID:
@@ -502,7 +556,7 @@ format_process_maps (_pinfo *p, char *destbuf, size_t maxsize)
 				st.st_ino);
 	while (written++ < 61)
 	  destbuf[len + written] = ' ';
-        len += written;
+        len += written - 1;
 	len += __small_sprintf (destbuf + len, "%s\n", posix_modname);
       }
 out:
diff --git a/winsup/cygwin/fhandler_registry.cc b/winsup/cygwin/fhandler_registry.cc
index c15882176..92f7f8e42 100644
--- a/winsup/cygwin/fhandler_registry.cc
+++ b/winsup/cygwin/fhandler_registry.cc
@@ -236,7 +236,7 @@ fhandler_registry::fstat (struct __stat64 *buf)
 	      buf->st_ctim = buf->st_mtim;
 	      time_as_timestruc_t (&buf->st_atim);
 	      if (file_type > 0)
-		buf->st_nlink = subkey_count;
+		buf->st_nlink = subkey_count + 2;
 	      else
 		{
 		  int pathlen = strlen (path);
diff --git a/winsup/cygwin/fhandler_socket.cc b/winsup/cygwin/fhandler_socket.cc
index 803ba44cb..a7e52936e 100644
--- a/winsup/cygwin/fhandler_socket.cc
+++ b/winsup/cygwin/fhandler_socket.cc
@@ -147,6 +147,15 @@ fhandler_socket::~fhandler_socket ()
     cfree (sun_path);
 }
 
+char *fhandler_socket::get_proc_fd_name (char *buf)
+{
+  if (get_sun_path ())
+    __small_sprintf (buf, "%s", get_sun_path ());
+  else
+    __small_sprintf (buf, "socket:[%d]", get_socket ());
+  return buf;
+}
+
 void
 fhandler_socket::set_connect_secret ()
 {
diff --git a/winsup/cygwin/path.cc b/winsup/cygwin/path.cc
index 0d2637537..5d5d1eade 100644
--- a/winsup/cygwin/path.cc
+++ b/winsup/cygwin/path.cc
@@ -3135,22 +3135,10 @@ symlink_info::check (char *path, const suffix_info *suffixes, unsigned opt)
 int
 symlink_info::set (char *path, int type)
 {
-  extern suffix_info stat_suffixes[];
-
   strcpy (contents, path);
   pflags = PATH_SYMLINK;
-  if (type == -3) /* /proc/self */
-    {
-      fileattr = FILE_ATTRIBUTE_DIRECTORY;
-      error = 0;
-    }
-  else
-    {
-      /* That's save since a virtual symlink doesn't point to itself. */
-      path_conv pc (contents, PC_SYM_NOFOLLOW | PC_FULL, stat_suffixes);
-      fileattr = pc;
-      error = pc.error;
-    }
+  fileattr = FILE_ATTRIBUTE_NORMAL;
+  error = 0;
   is_symlink = true;
   ext_tacked_on = case_clash = false;
   ext_here = NULL;
diff --git a/winsup/cygwin/pinfo.cc b/winsup/cygwin/pinfo.cc
index fa440aa39..6df0f5e0c 100644
--- a/winsup/cygwin/pinfo.cc
+++ b/winsup/cygwin/pinfo.cc
@@ -380,7 +380,7 @@ extern char **__argv;
 void
 _pinfo::commune_recv ()
 {
-  char pathbuf[CYG_MAX_PATH];
+  char path[CYG_MAX_PATH + 1];
   DWORD nr;
   DWORD code;
   HANDLE hp;
@@ -460,33 +460,78 @@ _pinfo::commune_recv ()
       }
     case PICOM_CWD:
       {
-	unsigned int n = strlen (cygheap->cwd.get (pathbuf, 1, 1, CYG_MAX_PATH)) + 1;
         CloseHandle (__fromthem); __fromthem = NULL;
 	CloseHandle (hp);
+	unsigned int n = strlen (cygheap->cwd.get (path, 1, 1,
+						   CYG_MAX_PATH)) + 1;
 	if (!WriteFile (__tothem, &n, sizeof n, &nr, NULL))
-	  sigproc_printf ("WriteFile sizeof argv failed, %E");
-	else if (!WriteFile (__tothem, pathbuf, n, &nr, NULL))
-	  sigproc_printf ("WriteFile sizeof argv failed, %E");
+	  sigproc_printf ("WriteFile sizeof cwd failed, %E");
+	else if (!WriteFile (__tothem, path, n, &nr, NULL))
+	  sigproc_printf ("WriteFile cwd failed, %E");
 	break;
       }
     case PICOM_ROOT:
       {
+        CloseHandle (__fromthem); __fromthem = NULL;
+	CloseHandle (hp);
 	unsigned int n;
 	if (cygheap->root.exists ())
-	  n = strlen (strcpy (pathbuf, cygheap->root.posix_path ())) + 1;
+	  n = strlen (strcpy (path, cygheap->root.posix_path ())) + 1;
 	else
-	  n = strlen (strcpy (pathbuf, "/")) + 1;
+	  n = strlen (strcpy (path, "/")) + 1;
+	if (!WriteFile (__tothem, &n, sizeof n, &nr, NULL))
+	  sigproc_printf ("WriteFile sizeof root failed, %E");
+	else if (!WriteFile (__tothem, path, n, &nr, NULL))
+	  sigproc_printf ("WriteFile root failed, %E");
+	break;
+      }
+    case PICOM_FDS:
+      {
         CloseHandle (__fromthem); __fromthem = NULL;
 	CloseHandle (hp);
+	unsigned int n = 0;
+	int fd;
+	cygheap_fdenum cfd;
+	while ((fd = cfd.next ()) >= 0)
+	  n += sizeof (int);
+	cfd.rewind ();
 	if (!WriteFile (__tothem, &n, sizeof n, &nr, NULL))
-	  sigproc_printf ("WriteFile sizeof argv failed, %E");
-	else if (!WriteFile (__tothem, pathbuf, n, &nr, NULL))
-	  sigproc_printf ("WriteFile sizeof argv failed, %E");
-	break;
+	  sigproc_printf ("WriteFile sizeof fds failed, %E");
+	else
+	  while ((fd = cfd.next ()) >= 0)
+	    if (!WriteFile (__tothem, &fd, sizeof fd, &nr, NULL))
+	      {
+		sigproc_printf ("WriteFile fd %d failed, %E", fd);
+		break;
+	      }
+        break;
+      }
+    case PICOM_FD:
+      {
+	int fd;
+	if (!ReadFile (__fromthem, &fd, sizeof fd, &nr, NULL)
+	    || nr != sizeof fd)
+	  {
+	    sigproc_printf ("ReadFile fd failed, %E");
+	    CloseHandle (hp);
+	    goto out;
+	  }
+	CloseHandle (__fromthem); __fromthem = NULL;
+	CloseHandle (hp);
+	unsigned int n;
+	cygheap_fdget cfd (fd);
+	if (cfd < 0)
+	  n = strlen (strcpy (path, "<disconnected>")) + 1;
+	else
+	  n = strlen (cfd->get_proc_fd_name (path)) + 1;
+	if (!WriteFile (__tothem, &n, sizeof n, &nr, NULL))
+	  sigproc_printf ("WriteFile sizeof fd failed, %E");
+	else if (!WriteFile (__tothem, path, n, &nr, NULL))
+	  sigproc_printf ("WriteFile fd failed, %E");
+        break;
       }
     case PICOM_FIFO:
       {
-	char path[CYG_MAX_PATH + 1];
 	unsigned len;
 	if (!ReadFile (__fromthem, &len, sizeof len, &nr, NULL)
 	    || nr != sizeof len)
@@ -614,9 +659,21 @@ _pinfo::commune_send (DWORD code, ...)
   size_t n;
   switch (code)
     {
+    case PICOM_FD:
+      {
+	int fd = va_arg (args, int);
+	if (!WriteFile (tothem, &fd, sizeof fd, &nr, NULL)
+	    || nr != sizeof fd)
+	  {
+	    __seterrno ();
+	    goto err;
+	  }
+      }
+      /*FALLTHRU*/
     case PICOM_CMDLINE:
     case PICOM_CWD:
     case PICOM_ROOT:
+    case PICOM_FDS:
       if (!ReadFile (fromthem, &n, sizeof n, &nr, NULL) || nr != sizeof n)
 	{
 	  __seterrno ();
@@ -684,6 +741,58 @@ out:
 }
 
 char *
+_pinfo::fd (int fd, size_t &n)
+{
+  char *s;
+  if (!this || !pid)
+    return NULL;
+  if (pid != myself->pid)
+    {
+      commune_result cr = commune_send (PICOM_FD, fd);
+      s = cr.s;
+      n = cr.n;
+    }
+  else
+    {
+      cygheap_fdget cfd (fd);
+      if (cfd < 0)
+	s = strdup ("<disconnected>");
+      else
+	s = cfd->get_proc_fd_name ((char *) malloc (CYG_MAX_PATH + 1));
+      n = strlen (s) + 1;
+    }
+  return s;
+}
+
+char *
+_pinfo::fds (size_t &n)
+{
+  char *s;
+  if (!this || !pid)
+    return NULL;
+  if (pid != myself->pid)
+    {
+      commune_result cr = commune_send (PICOM_FDS);
+      s = cr.s;
+      n = cr.n;
+    }
+  else
+    {
+      n = 0;
+      int fd;
+      cygheap_fdenum cfd;
+      while ((fd = cfd.next ()) >= 0)
+	n += sizeof (int);
+      cfd.rewind ();
+      s = (char *) malloc (n);
+      int *p = (int *) s;
+      while ((fd = cfd.next ()) >= 0 && (char *) p - s < (int) n)
+	*p++ = fd;
+    }
+  return s;
+}
+
+char *
 _pinfo::root (size_t& n)
 {
   char *s;
diff --git a/winsup/cygwin/pinfo.h b/winsup/cygwin/pinfo.h
index 88442ca22..705a1a599 100644
--- a/winsup/cygwin/pinfo.h
+++ b/winsup/cygwin/pinfo.h
@@ -25,7 +25,9 @@ enum picom
   PICOM_CMDLINE = 1,
   PICOM_FIFO = 2,
   PICOM_CWD = 3,
-  PICOM_ROOT = 4
+  PICOM_ROOT = 4,
+  PICOM_FDS = 5,
+  PICOM_FD = 6
 };
 
 #define EXITCODE_SET 0x80000000
@@ -108,6 +110,8 @@ public:
   void commune_recv ();
   commune_result commune_send (DWORD, ...);
   bool alive ();
+  char *fd (int fd, size_t &);
+  char *fds (size_t &);
   char *root (size_t &);
   char *cwd (size_t &);
   char *cmdline (size_t &);
diff --git a/winsup/cygwin/pipe.cc b/winsup/cygwin/pipe.cc
index ad5131d36..c2d633afc 100644
--- a/winsup/cygwin/pipe.cc
+++ b/winsup/cygwin/pipe.cc
@@ -53,6 +53,12 @@ fhandler_pipe::set_close_on_exec (bool val)
     set_no_inheritance (writepipe_exists, val);
 }
 
+char *fhandler_pipe::get_proc_fd_name (char *buf)
+{
+  __small_sprintf (buf, "pipe:[%d]", get_handle ());
+  return buf;
+}
+
 struct pipeargs
 {
   fhandler_base *fh;