# HG changeset patch
# User Binki <ohnobinki@ohnopublishing.net>
# Date 2009-03-16 23:11:35
# Node ID 7b322e60270cc92f27cbd95b398eeb42bd59c535
# Parent  2e10900d91d9eebc8e97ed748b10cc214089eae2

a few polishes to execio

maybe we're ready to start working on:
common configfile setup
and then remoteio, which uses the configfile

diff --git a/src/common/execio.c b/src/common/execio.c
--- a/src/common/execio.c
+++ b/src/common/execio.c
@@ -26,6 +26,7 @@
 #include <malloc.h>
 #include <fcntl.h>
 #include <stdio.h>
+#include <errno.h>
 
 int execio_open(struct execio **rem, const char *progname, char *const argv[])
 {
@@ -182,12 +183,30 @@ int execio_read(struct execio *eio, void
 
 int execio_write(struct execio *eio, void *buf, size_t len, size_t *bytesread)
 {
-  /*
-    TODO: errno handling
-   */
+  errno = 0;
   (*bytesread) = write(eio->pipe_write, buf, len);
   if(!*bytesread)
-    eio->state = EXECIO_STATE_ERROR;
+    {
+      switch(errno)
+	{
+	case EPIPE:
+	  /* 
+	     the program closed the pipe (died)
+	  */
+	fprintf(stderr, "execio_write: the child program closed its stdin pipe\n");
+	eio->state = EXECIO_STATE_EOF;
+	break;
+	
+	default:
+	  fprintf(stderr, "execio_write: unhandled error writing to an fd: \n");
+	  perror("write");
+	  eio->state = EXECIO_STATE_ERROR;
+	  break;
+	  
+	}
+      
+      return 1;
+    }
 
   return 0;
 }
@@ -208,7 +227,11 @@ int execio_close(struct execio *eio)
 
   /* maybe we should just kill the child */
   kill(eio->child, SIGTERM);
-  /* the waitpid(2) seems to indicate that only when the child is terminated will this wait return. */
+  /* 
+     the waitpid(2) seems to indicate that only when the child is terminated will this wait return. 
+     This are of code will probably need improving - the ability to seng SIGKILL after a timeout? So we'll output a debug line before running waitpid
+  */
+  fprintf(stderr, "execio_close: running waitpid\n");
   waitpid(eio->child, &childstatus, 0);
   
   return 0;
diff --git a/src/common/execio.h b/src/common/execio.h
--- a/src/common/execio.h
+++ b/src/common/execio.h
@@ -57,9 +57,14 @@ int execio_open(struct execio **rem, con
 int execio_read(struct execio *eio, void *buf, size_t len, size_t *bytesread);
 int execio_write(struct execio *eio, void *buf, size_t len, size_t *bytesread);
 
+/*
+  use this function to determine if the using program should keep trying to read/write
+ */
 enum execio_state execio_state(struct execio *eio);
 
-/* nonzero return on error */
+/* 
+   nonzero return on error 
+*/
 int execio_close(struct execio *eio);
 
 #endif