pex-unix.c (pex_child_error): Improve warning avoidance by checking the results…

pex-unix.c (pex_child_error): Improve warning avoidance by checking the results of write(3) and exiting with...

	* pex-unix.c (pex_child_error): Improve warning avoidance by
	checking the results of write(3) and exiting with -2 if any write
	returns a negative value.

Co-Authored-By: Ian Lance Taylor <iant@google.com>

From-SVN: r154431

libiberty/ChangeLog

+2009-11-23  Ben Elliston  <bje@au.ibm.com>
+	    Ian Lance Taylor  <iant@google.com>
+
+	* pex-unix.c (pex_child_error): Improve warning avoidance by
+	checking the results of write(3) and exiting with -2 if any write
+	returns a negative value.
+
 2009-11-22  Steve Ward  <planet36@gmail.com>
 
 	* dyn-string.c (dyn_string_append_char): Fix typo in comment.

libiberty/pex-unix.c

@@ -368,7 +368,8 @@ static void
 pex_child_error (struct pex_obj *obj, const char *executable,
 		 const char *errmsg, int err)
 {
-#define writeerr(s) if (write (STDERR_FILE_NO, s, strlen (s))) {}
+  int retval = 0;
+#define writeerr(s) retval |= (write (STDERR_FILE_NO, s, strlen (s)) < 0)
   writeerr (obj->pname);
   writeerr (": error trying to exec '");
   writeerr (executable);
@@ -378,7 +379,8 @@ pex_child_error (struct pex_obj *obj, const char *executable,
   writeerr (xstrerror (err));
   writeerr ("\n");
 #undef writeerr
-  _exit (-1);
+  /* Exit with -2 if the error output failed, too.  */
+  _exit (retval == 0 ? -1 : -2);
 }
 
 /* Execute a child.  */