include/binutils-csl-palmsource-arm-prelinker-1_0-1

	* libiberty.h: Declare pex_run_in_environment.

	libiberty/
	* pex-common.c: New function pex_run_in_environment.
	* pex-common.h: Add environment parameter to exec_child.
	* pex-msdos.c: Add environment parameter to pex_msdos_exec_child.
	* pex-djgpp.c: Add environment parameter to pex_djgpp_exec_child.
	(pex_djgpp_exec_child): Pass environment to child process.
	* pex-unix.c: Add environment parameter to pex_unix_exec_child.
	(pex_unix_exec_child): Pass environment to child process.
	* pex-win32.c: Add environment parameter to pex_win32_exec_child.
	New function env_compare for comparing VAR=VALUE pairs.
	(win32_spawn): Assemble environment block and pass to CreateProcess.
	(spawn_script): Pass environment through to win32_spawn.
	(pex_win32_exec_child): Pass environment through to spawn_script and
	win32_spawn.
	* functions.texi: Regenerate.
	* pexecute.txh: Document pex_run_in_environment.

10 files changed, 222 insertions, 36 deletions

diff --git a/ChangeLog.csl b/ChangeLog.csl
index cf7b0ba8d3..8fcce895bb 100644
--- a/ChangeLog.csl
+++ b/ChangeLog.csl
@@ -1,3 +1,25 @@
+2006-09-28  Mark Shinwell  <shinwell@codesourcery.com>
+
+	include/
+	* libiberty.h: Declare pex_run_in_environment.
+
+	libiberty/  
+	* pex-common.c: New function pex_run_in_environment.
+	* pex-common.h: Add environment parameter to exec_child.
+	* pex-msdos.c: Add environment parameter to pex_msdos_exec_child.
+	* pex-djgpp.c: Add environment parameter to pex_djgpp_exec_child.
+	(pex_djgpp_exec_child): Pass environment to child process.
+	* pex-unix.c: Add environment parameter to pex_unix_exec_child.
+	(pex_unix_exec_child): Pass environment to child process.
+	* pex-win32.c: Add environment parameter to pex_win32_exec_child.
+	New function env_compare for comparing VAR=VALUE pairs.
+	(win32_spawn): Assemble environment block and pass to CreateProcess.
+	(spawn_script): Pass environment through to win32_spawn.
+	(pex_win32_exec_child): Pass environment through to spawn_script and
+	win32_spawn.
+	* functions.texi: Regenerate.
+	* pexecute.txh: Document pex_run_in_environment.
+
 2006-09-19  Mark Shinwell  <shinwell@codesourcery.com>
             Joseph Myers  <joseph@codesourcery.com>
             Ian Lance Taylor  <ian@wasabisystems.com>
diff --git a/include/libiberty.h b/include/libiberty.h
index 6bd318e0fe..1328d3eb14 100644
--- a/include/libiberty.h
+++ b/include/libiberty.h
@@ -448,6 +448,23 @@ extern const char *pex_run (struct pex_obj *obj, int flags,
 			    const char *outname, const char *errname,
 			    int *err);
 
+/* As for pex_run (), but takes an extra parameter to enable the
+   environment for the child process to be specified.
+
+   ENV		The environment for the child process, specified as
+		an array of character pointers.  Each element of the
+		array should point to a string of the form VAR=VALUE,
+                with the exception of the last element which must be
+                a null pointer.
+*/
+
+extern const char *pex_run_in_environment (struct pex_obj *obj, int flags,
+			                   const char *executable,
+                                           char * const *argv,
+                                           char * const *env,
+              	          		   const char *outname,
+					   const char *errname, int *err);
+
 /* Return a `FILE' pointer FP for the standard input of the first
    program in the pipeline; FP is opened for writing.  You must have
    passed `PEX_USE_PIPES' to the `pex_init' call that returned OBJ.
diff --git a/libiberty/functions.texi b/libiberty/functions.texi
index 9696df3f2e..d10a4a0928 100644
--- a/libiberty/functions.texi
+++ b/libiberty/functions.texi
@@ -668,14 +668,14 @@ reading and writing.
 
 @end deftypefn
 
-@c pexecute.txh:259
+@c pexecute.txh:272
 @deftypefn Extension void pex_free (struct pex_obj @var{obj})
 
 Clean up and free all data associated with @var{obj}.
 
 @end deftypefn
 
-@c pexecute.txh:234
+@c pexecute.txh:247
 @deftypefn Extension int pex_get_status (struct pex_obj *@var{obj}, int @var{count}, int *@var{vector})
 
 Returns the exit status of all programs run using @var{obj}.
@@ -685,7 +685,7 @@ to @code{pex_run}.  Returns 0 on error, 1 on success.
 
 @end deftypefn
 
-@c pexecute.txh:243
+@c pexecute.txh:256
 @deftypefn Extension int pex_get_times (struct pex_obj *@var{obj}, int @var{count}, struct pex_time *@var{vector})
 
 Returns the process execution times of all programs run using
@@ -734,7 +734,7 @@ temporary files; it may be @code{NULL} to use a randomly chosen name.
 
 @end deftypefn
 
-@c pexecute.txh:161
+@c pexecute.txh:174
 @deftypefn Extension {FILE *} pex_input_file (struct pex_obj *@var{obj}, int @var{flags}, const char *@var{in_name})
 
 Return a stream for a temporary file to pass to the first program in
@@ -752,7 +752,7 @@ binary mode; otherwise, open it in the default mode.  Including
 @code{PEX_BINARY_OUTPUT} in @var{flags} has no effect on Unix.
 @end deftypefn
 
-@c pexecute.txh:178
+@c pexecute.txh:191
 @deftypefn Extension {FILE *} pex_input_pipe (struct pex_obj *@var{obj}, int @var{binary})
 
 Return a stream @var{fp} for a pipe connected to the standard input of
@@ -797,7 +797,7 @@ the output pipe is you, but you are blocked on the input pipe.
 
 @end deftypefn
 
-@c pexecute.txh:265
+@c pexecute.txh:278
 @deftypefn Extension {const char *} pex_one (int @var{flags}, const char *@var{executable}, char * const *@var{argv}, const char *@var{pname}, const char *@var{outname}, const char *@var{errname}, int *@var{status}, int *@var{err})
 
 An interface to permit the easy execution of a
@@ -810,7 +810,7 @@ be set to the exit status of the program.
 
 @end deftypefn
 
-@c pexecute.txh:222
+@c pexecute.txh:235
 @deftypefn Extension {FILE *} pex_read_output (struct pex_obj *@var{obj}, int @var{binary})
 
 Returns a @code{FILE} pointer which may be used to read the standard
@@ -924,6 +924,20 @@ value, or to 0 if there is no relevant @code{errno}.
 
 @end deftypefn
 
+@c pexecute.txh:161
+@deftypefn Extension {const char *} pex_run_in_environment (struct pex_obj *@var{obj}, int @var{flags}, const char *@var{executable}, char * const *@var{argv}, char * const *@var{env}, int @var{env_size}, const char *@var{outname}, const char *@var{errname}, int *@var{err})
+
+Execute one program in a pipeline, permitting the environment for the
+program to be specified.  Behaviour and parameters not listed below are
+as for @code{pex_run}.
+
+@var{env} is the environment for the child process, specified as an array of
+character pointers.  Each element of the array should point to a string of the
+form @code{VAR=VALUE}, with the exception of the last element that must be
+@code{NULL}.
+
+@end deftypefn
+
 @c pexecute.txh:133
 @deftypefn Extension {FILE *} pex_write_input (struct pex_obj *@var{obj}, int @var{binary})
 
@@ -953,7 +967,7 @@ the output pipe is you, but you are blocked on the input pipe.
 
 @end deftypefn
 
-@c pexecute.txh:277
+@c pexecute.txh:290
 @deftypefn Extension int pexecute (const char *@var{program}, char * const *@var{argv}, const char *@var{this_pname}, const char *@var{temp_base}, char **@var{errmsg_fmt}, char **@var{errmsg_arg}, int flags)
 
 This is the old interface to execute one or more programs.  It is
@@ -981,7 +995,7 @@ name is unset/removed.
 
 @end deftypefn
 
-@c pexecute.txh:285
+@c pexecute.txh:298
 @deftypefn Extension int pwait (int @var{pid}, int *@var{status}, int @var{flags})
 
 Another part of the old execution interface.
diff --git a/libiberty/pex-common.c b/libiberty/pex-common.c
index bce2c3b428..e4c063dc69 100644
--- a/libiberty/pex-common.c
+++ b/libiberty/pex-common.c
@@ -142,12 +142,15 @@ temp_file (struct pex_obj *obj, int flags, char *name)
   return name;
 }
 
-/* Run a program.  */
+
+/* As for pex_run (), but permits the environment for the child process
+   to be specified. */
 
 const char *
-pex_run (struct pex_obj *obj, int flags, const char *executable,
-	 char * const * argv, const char *orig_outname, const char *errname,
-	 int *err)
+pex_run_in_environment (struct pex_obj *obj, int flags, const char *executable,
+       	                char * const * argv, char * const * env,
+                        const char *orig_outname, const char *errname,
+                  	int *err)
 {
   const char *errmsg;
   int in, out, errdes;
@@ -298,8 +301,8 @@ pex_run (struct pex_obj *obj, int flags, const char *executable,
 
   /* Run the program.  */
 
-  pid = obj->funcs->exec_child (obj, flags, executable, argv, in, out, errdes,
-				&errmsg, err);
+  pid = obj->funcs->exec_child (obj, flags, executable, argv, env,
+                                in, out, errdes, &errmsg, err);
   if (p[WRITE_PORT] != -1)
     obj->funcs->close (obj, p[WRITE_PORT]);
   if (pid < 0)
@@ -369,6 +372,17 @@ pex_write_input (struct pex_obj *obj, int binary)
   return NULL;
 }
 
+/* Run a program.  */
+
+const char *
+pex_run (struct pex_obj *obj, int flags, const char *executable,
+       	 char * const * argv, const char *orig_outname, const char *errname,
+         int *err)
+{
+  return pex_run_in_environment (obj, flags, executable, argv, NULL,
+				 orig_outname, errname, err);
+}
+
 /* Return a FILE pointer for a temporary file to fill with input for
    the pipeline.  */
 FILE *
diff --git a/libiberty/pex-common.h b/libiberty/pex-common.h
index 8ded138148..520f26a260 100644
--- a/libiberty/pex-common.h
+++ b/libiberty/pex-common.h
@@ -104,6 +104,7 @@ struct pex_funcs
      error and set *ERRMSG and *ERR.  */
   long (*exec_child) (struct pex_obj *, int /* flags */,
                       const char */* executable */, char * const * /* argv */,
+                      char * const * /* env */,
                       int /* in */, int /* out */, int /* errdes */,
 		      const char **/* errmsg */, int */* err */);
   /* Close a descriptor.  Return 0 on success, -1 on error.  */
diff --git a/libiberty/pex-djgpp.c b/libiberty/pex-djgpp.c
index 17fbf2cc7e..acaa4c43fd 100644
--- a/libiberty/pex-djgpp.c
+++ b/libiberty/pex-djgpp.c
@@ -45,7 +45,8 @@ extern int errno;
 static int pex_djgpp_open_read (struct pex_obj *, const char *, int);
 static int pex_djgpp_open_write (struct pex_obj *, const char *, int);
 static long pex_djgpp_exec_child (struct pex_obj *, int, const char *,
-				  char * const *, int, int, int,
+				  char * const *, char * const *,
+                                  int, int, int,
 				  const char **, int *);
 static int pex_djgpp_close (struct pex_obj *, int);
 static int pex_djgpp_wait (struct pex_obj *, long, int *, struct pex_time *,
@@ -111,7 +112,8 @@ pex_djgpp_close (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd)
 
 static long
 pex_djgpp_exec_child (struct pex_obj *obj, int flags, const char *executable,
-		      char * const * argv, int in, int out, int errdes,
+		      char * const * argv, char * const * env,
+                      int in, int out, int errdes,
 		      const char **errmsg, int *err)
 {
   int org_in, org_out, org_errdes;
@@ -196,8 +198,12 @@ pex_djgpp_exec_child (struct pex_obj *obj, int flags, const char *executable,
 	}
     }
 
-  status = (((flags & PEX_SEARCH) != 0 ? spawnvp : spawnv)
-	    (P_WAIT, executable, (char * const *) argv));
+  if (env)
+    status = (((flags & PEX_SEARCH) != 0 ? spawnvpe : spawnve)
+	      (P_WAIT, executable, argv, env));
+  else
+    status = (((flags & PEX_SEARCH) != 0 ? spawnvp : spawnv)
+  	      (P_WAIT, executable, argv));
 
   if (status == -1)
     {
diff --git a/libiberty/pex-msdos.c b/libiberty/pex-msdos.c
index db22337aa2..bcad93dbe2 100644
--- a/libiberty/pex-msdos.c
+++ b/libiberty/pex-msdos.c
@@ -55,8 +55,8 @@ static int pex_msdos_open (struct pex_obj *, const char *, int);
 static int pex_msdos_open (struct pex_obj *, const char *, int);
 static int pex_msdos_fdindex (struct pex_msdos *, int);
 static long pex_msdos_exec_child (struct pex_obj *, int, const char *,
-				  char * const *, int, int, int,
-				  const char **, int *);
+				  char * const *, char * const *,
+                                  int, int, int, const char **, int *);
 static int pex_msdos_close (struct pex_obj *, int);
 static int pex_msdos_wait (struct pex_obj *, long, int *, struct pex_time *,
 			   int, const char **, int *);
@@ -153,7 +153,7 @@ pex_msdos_close (struct pex_obj *obj, int fd)
 
 static long
 pex_msdos_exec_child (struct pex_obj *obj, int flags, const char *executable,
-		      char * const * argv, int in, int out,
+		      char * const * argv, char * const * env, int in, int out,
 		      int errdes ATTRIBUTE_UNUSED, const char **errmsg,
 		      int *err)
 {
diff --git a/libiberty/pex-unix.c b/libiberty/pex-unix.c
index c92a429797..91619af1e2 100644
--- a/libiberty/pex-unix.c
+++ b/libiberty/pex-unix.c
@@ -270,8 +270,8 @@ static void pex_child_error (struct pex_obj *, const char *, const char *, int)
 static int pex_unix_open_read (struct pex_obj *, const char *, int);
 static int pex_unix_open_write (struct pex_obj *, const char *, int);
 static long pex_unix_exec_child (struct pex_obj *, int, const char *,
-				 char * const *, int, int, int,
-				 const char **, int *);
+				 char * const *, char * const *,
+                                 int, int, int, const char **, int *);
 static int pex_unix_close (struct pex_obj *, int);
 static int pex_unix_wait (struct pex_obj *, long, int *, struct pex_time *,
 			  int, const char **, int *);
@@ -352,12 +352,16 @@ pex_child_error (struct pex_obj *obj, const char *executable,
 
 /* Execute a child.  */
 
+extern char **environ;
+
 static long
 pex_unix_exec_child (struct pex_obj *obj, int flags, const char *executable,
-		     char * const * argv, int in, int out, int errdes,
+		     char * const * argv, char * const * env,
+                     int in, int out, int errdes,
 		     const char **errmsg, int *err)
 {
   pid_t pid;
+
   /* We declare these to be volatile to avoid warnings from gcc about
      them being clobbered by vfork.  */
   volatile int sleep_interval;
@@ -409,6 +413,10 @@ pex_unix_exec_child (struct pex_obj *obj, int flags, const char *executable,
 	  if (dup2 (STDOUT_FILE_NO, STDERR_FILE_NO) < 0)
 	    pex_child_error (obj, executable, "dup2", errno);
 	}
+
+      if (env)
+        environ = env;
+
       if ((flags & PEX_SEARCH) != 0)
 	{
 	  execvp (executable, argv);
diff --git a/libiberty/pex-win32.c b/libiberty/pex-win32.c
index 046f393c6d..45725457b6 100644
--- a/libiberty/pex-win32.c
+++ b/libiberty/pex-win32.c
@@ -36,12 +36,14 @@ Boston, MA 02110-1301, USA.  */
 #include <sys/wait.h>
 #endif
 
+#include <assert.h>
 #include <process.h>
 #include <io.h>
 #include <fcntl.h>
 #include <signal.h>
 #include <sys/stat.h>
 #include <errno.h>
+#include <ctype.h>
 
 /* mingw32 headers may not define the following.  */
 
@@ -59,6 +61,8 @@ Boston, MA 02110-1301, USA.  */
 #define MINGW_NAME "Minimalist GNU for Windows"
 #define MINGW_NAME_LEN (sizeof(MINGW_NAME) - 1)
 
+extern char *stpcpy (char *dst, const char *src);
+
 /* Ensure that the executable pathname uses Win32 backslashes. This
    is not necessary on NT, but on W9x, forward slashes causes
    failure of spawn* and exec* functions (and probably any function
@@ -76,7 +80,8 @@ backslashify (char *s)
 static int pex_win32_open_read (struct pex_obj *, const char *, int);
 static int pex_win32_open_write (struct pex_obj *, const char *, int);
 static long pex_win32_exec_child (struct pex_obj *, int, const char *,
-				  char * const *, int, int, int,
+				  char * const *, char * const *,
+                                  int, int, int,
 				  const char **, int *);
 static int pex_win32_close (struct pex_obj *, int);
 static int pex_win32_wait (struct pex_obj *, long, int *,
@@ -478,22 +483,96 @@ find_executable (const char *program, BOOL search)
   return full_executable;
 }
 
-/* Low-level process creation function.  */
+/* Low-level process creation function and helper.  */
+
+static int
+env_compare (const void *a_ptr, const void *b_ptr)
+{
+  const char *a;
+  const char *b;
+  unsigned char c1;
+  unsigned char c2;
+
+  a = *(const char **) a_ptr;
+  b = *(const char **) b_ptr;
+
+  /* a and b will be of the form: VAR=VALUE
+     We compare only the variable name part here using a case-insensitive
+     comparison algorithm.  It might appear that in fact strcasecmp () can
+     take the place of this whole function, and indeed it could, save for
+     the fact that it would fail in cases such as comparing A1=foo and
+     A=bar (because 1 is less than = in the ASCII character set).
+     (Environment variables containing no numbers would work in such a
+     scenario.)  */
+
+  do
+    {
+      c1 = (unsigned char) tolower (*a++);
+      c2 = (unsigned char) tolower (*b++);
+
+      if (c1 == '=')
+        c1 = '\0';
+
+      if (c2 == '=')
+        c2 = '\0';
+    }
+  while (c1 == c2 && c1 != '\0');
+
+  return c1 - c2;
+}
 
 static long
 win32_spawn (const char *executable,
 	     BOOL search,
 	     char *const *argv,
+             char *const *env, /* array of strings of the form: VAR=VALUE */
 	     DWORD dwCreationFlags,
 	     LPSTARTUPINFO si,
 	     LPPROCESS_INFORMATION pi)
 {
   char *full_executable;
   char *cmdline;
+  char **env_copy;
+  char *env_block = NULL;
 
   full_executable = NULL;
   cmdline = NULL;
 
+  if (env)
+    {
+      int env_size;
+
+      /* Count the number of environment bindings supplied.  */
+      for (env_size = 0; env[env_size]; env_size++)
+        continue;
+    
+      /* Assemble an environment block, if required.  This consists of
+         VAR=VALUE strings juxtaposed (with one null character between each
+         pair) and an additional null at the end.  */
+      if (env_size > 0)
+        {
+          int var;
+          int total_size = 1; /* 1 is for the final null.  */
+          char *bufptr;
+    
+          /* Windows needs the members of the block to be sorted by variable
+             name.  */
+          env_copy = alloca (sizeof (char *) * env_size);
+          memcpy (env_copy, env, sizeof (char *) * env_size);
+          qsort (env_copy, env_size, sizeof (char *), env_compare);
+    
+          for (var = 0; var < env_size; var++)
+            total_size += strlen (env[var]) + 1;
+    
+          env_block = malloc (total_size);
+          bufptr = env_block;
+          for (var = 0; var < env_size; var++)
+            bufptr = stpcpy (bufptr, env_copy[var]) + 1;
+    
+          *bufptr = '\0';
+        }
+    }
+
   full_executable = find_executable (executable, search);
   if (!full_executable)
     goto error;
@@ -507,31 +586,41 @@ win32_spawn (const char *executable,
 		      /*lpThreadAttributes=*/NULL,
 		      /*bInheritHandles=*/TRUE,
 		      dwCreationFlags,
-		      /*lpEnvironment=*/NULL,
+		      (LPVOID) env_block,
 		      /*lpCurrentDirectory=*/NULL,
 		      si,
 		      pi))
     {
+      if (env_block)
+        free (env_block);
+
       free (full_executable);
+
       return -1;
     }
 
   /* Clean up.  */
   CloseHandle (pi->hThread);
   free (full_executable);
+  if (env_block)
+    free (env_block);
 
   return (long) pi->hProcess;
 
  error:
+  if (env_block)
+    free (env_block);
   if (cmdline)
     free (cmdline);
   if (full_executable)
     free (full_executable);
+
   return -1;
 }
 
 static long
 spawn_script (const char *executable, char *const *argv,
+              char* const *env,
 	      DWORD dwCreationFlags,
 	      LPSTARTUPINFO si,
 	      LPPROCESS_INFORMATION pi)
@@ -566,20 +655,20 @@ spawn_script (const char *executable, char *const *argv,
 	      executable = strrchr (executable1, '\\') + 1;
 	      if (!executable)
 		executable = executable1;
-	      pid = win32_spawn (executable, TRUE, argv, 
+	      pid = win32_spawn (executable, TRUE, argv, env,
 				 dwCreationFlags, si, pi);
 #else
 	      if (strchr (executable1, '\\') == NULL)
-		pid = win32_spawn (executable1, TRUE, argv, 
+		pid = win32_spawn (executable1, TRUE, argv, env,
 				   dwCreationFlags, si, pi);
 	      else if (executable1[0] != '\\')
-		pid = win32_spawn (executable1, FALSE, argv, 
+		pid = win32_spawn (executable1, FALSE, argv, env,
 				   dwCreationFlags, si, pi);
 	      else
 		{
 		  const char *newex = mingw_rootify (executable1);
 		  *avhere = newex;
-		  pid = win32_spawn (newex, FALSE, argv, 
+		  pid = win32_spawn (newex, FALSE, argv, env,
 				     dwCreationFlags, si, pi);
 		  if (executable1 != newex)
 		    free ((char *) newex);
@@ -589,7 +678,7 @@ spawn_script (const char *executable, char *const *argv,
 		      if (newex != executable1)
 			{
 			  *avhere = newex;
-			  pid = win32_spawn (newex, FALSE, argv, 
+			  pid = win32_spawn (newex, FALSE, argv, env,
 					     dwCreationFlags, si, pi);
 			  free ((char *) newex);
 			}
@@ -609,6 +698,7 @@ spawn_script (const char *executable, char *const *argv,
 static long
 pex_win32_exec_child (struct pex_obj *obj ATTRIBUTE_UNUSED, int flags,
 		      const char *executable, char * const * argv,
+                      char* const* env,
 		      int in, int out, int errdes, const char **errmsg,
 		      int *err)
 {
@@ -686,9 +776,10 @@ pex_win32_exec_child (struct pex_obj *obj ATTRIBUTE_UNUSED, int flags,
 
   /* Create the child process.  */  
   pid = win32_spawn (executable, (flags & PEX_SEARCH) != 0,
-		     argv, dwCreationFlags, &si, &pi);
+		     argv, env, dwCreationFlags, &si, &pi);
   if (pid == -1)
-    pid = spawn_script (executable, argv, dwCreationFlags, &si, &pi);
+    pid = spawn_script (executable, argv, env, dwCreationFlags,
+                        &si, &pi);
   if (pid == -1)
     {
       *err = ENOENT;
@@ -789,7 +880,7 @@ main (int argc ATTRIBUTE_UNUSED, char **argv)
   char const *errmsg;
   int err;
   argv++;
-  printf ("%ld\n", pex_win32_exec_child (NULL, PEX_SEARCH, argv[0], argv, 0, 1, 2, &errmsg, &err));
+  printf ("%ld\n", pex_win32_exec_child (NULL, PEX_SEARCH, argv[0], argv, NULL, 0, 0, 1, 2, &errmsg, &err));
   exit (0);
 }
 #endif
diff --git a/libiberty/pexecute.txh b/libiberty/pexecute.txh
index e3f1248407..d7745f2122 100644
--- a/libiberty/pexecute.txh
+++ b/libiberty/pexecute.txh
@@ -158,6 +158,19 @@ the output pipe is you, but you are blocked on the input pipe.
 
 @end deftypefn
 
+@deftypefn Extension {const char *} pex_run_in_environment (struct pex_obj *@var{obj}, int @var{flags}, const char *@var{executable}, char * const *@var{argv}, char * const *@var{env}, int @var{env_size}, const char *@var{outname}, const char *@var{errname}, int *@var{err})
+
+Execute one program in a pipeline, permitting the environment for the
+program to be specified.  Behaviour and parameters not listed below are
+as for @code{pex_run}.
+
+@var{env} is the environment for the child process, specified as an array of
+character pointers.  Each element of the array should point to a string of the
+form @code{VAR=VALUE}, with the exception of the last element that must be
+@code{NULL}.
+
+@end deftypefn
+
 @deftypefn Extension {FILE *} pex_input_file (struct pex_obj *@var{obj}, int @var{flags}, const char *@var{in_name})
 
 Return a stream for a temporary file to pass to the first program in