Assume POSIX 1003.1-1988 or later for errno.h.

* lib-src/movemail.c (main): Assume EAGAIN and EBUSY.
* src/dired.c (directory_files_internal, file_name_completion):
Assume EAGAIN and EINTR are defined.
* src/fileio.c (Fcopy_file): Assume EISDIR is defined.
* src/gmalloc.c (ENOMEM, EINVAL): Assume they're defined.
* src/gnutls.c (emacs_gnutls_write): Assume EAGAIN is defined.
* src/lread.c (readbyte_from_file): Assume EINTR is defined.
* src/process.c (wait_reading_process_output, send_process) [subprocesses]:
Assume EIO and EAGAIN are defined.
* src/unexcoff.c (write_segment): Assume EFAULT is defined.

Fixes: debbugs:12968

1 files changed, 2 insertions, 11 deletions

diff --git a/src/process.c b/src/process.c
index 0036ce595f5..b23f06fd025 100644
--- a/src/process.c
+++ b/src/process.c
@@ -4432,14 +4432,8 @@ wait_reading_process_output (intmax_t time_limit, int nsecs, int read_kbd,
                   total_nread += nread;
                   got_some_input = 1;
                 }
-#ifdef EIO
-              else if (nread == -1 && EIO == errno)
+              else if (nread == -1 && (errno == EIO || errno == EAGAIN))
                 break;
-#endif
-#ifdef EAGAIN
-              else if (nread == -1 && EAGAIN == errno)
-                break;
-#endif
 #ifdef EWOULDBLOCK
               else if (nread == -1 && EWOULDBLOCK == errno)
                 break;
@@ -5517,13 +5511,10 @@ send_process (Lisp_Object proc, const char *buf, ptrdiff_t len,
 
           if (rv < 0)
             {
-              if (0
+              if (errno == EAGAIN
 #ifdef EWOULDBLOCK
                   || errno == EWOULDBLOCK
 #endif
-#ifdef EAGAIN
-                  || errno == EAGAIN
-#endif
                   )
                 /* Buffer is full.  Wait, accepting input;
                    that may allow the program