Check return values of functions declared with warn_unused_result

attribute in GLIBC 2.8.
* cli/cli-cmds.c (pwd_command): Check return value from getcwd.
* inflow.c (check_syscall): New function.
(new_tty): Use check_syscall to check return values from open and dup.
* linux-nat.c (linux_nat_info_proc_cmd): Check return value from fgets.
* main.c (captured_main): Call cwd after setting up gdb_stderr;
check for errors from getcwd.
* mi/mi-cmd-env.c (mi_cmd_env_pwd): Check return value from getcwd.
* ui-file.c (stdio_file_write): Ignore return value from fwrite.
(stdio_file_fputs): Same.
* utils.c (internal_vproblem): abort if last-ditch error message
write fails.

1 files changed, 18 insertions, 8 deletions

diff --git a/gdb/inflow.c b/gdb/inflow.c
index a7cb25f3c82..972b52ef733 100644
--- a/gdb/inflow.c
+++ b/gdb/inflow.c
@@ -523,6 +523,20 @@ new_tty_prefork (const char *ttyname)
   inferior_thisrun_terminal = ttyname;
 }
 
+
+/* If RESULT, assumed to be the return value from a system call, is
+   negative, print the error message indicated by errno and exit.
+   MSG should identify the operation that failed.  */
+static void
+check_syscall (const char *msg, int result)
+{
+  if (result < 0)
+    {
+      print_sys_errmsg (msg, errno);
+      _exit (1);
+    }
+}
+
 void
 new_tty (void)
 {
@@ -549,27 +563,23 @@ new_tty (void)
 
   /* Now open the specified new terminal.  */
   tty = open (inferior_thisrun_terminal, O_RDWR | O_NOCTTY);
-  if (tty == -1)
-    {
-      print_sys_errmsg (inferior_thisrun_terminal, errno);
-      _exit (1);
-    }
+  check_syscall (inferior_thisrun_terminal, tty);
 
   /* Avoid use of dup2; doesn't exist on all systems.  */
   if (tty != 0)
     {
       close (0);
-      dup (tty);
+      check_syscall ("dup'ing tty into fd 0", dup (tty));
     }
   if (tty != 1)
     {
       close (1);
-      dup (tty);
+      check_syscall ("dup'ing tty into fd 1", dup (tty));
     }
   if (tty != 2)
     {
       close (2);
-      dup (tty);
+      check_syscall ("dup'ing tty into fd 2", dup (tty));
     }
 
 #ifdef TIOCSCTTY