commit 81ced45bf58750e563a5d90efa809edb39fb7c9a
author Denton Gentry <dgentry@google.com> Wed Jun 01 07:15:01 2016 -0700
committer Denton Gentry <dgentry@google.com> Wed Jun 01 19:16:48 2016 -0700
tree 3fc796ab6d92399e20f6b27d7616aae5ab227400
parent 6183527fc925e4cea8deeafa2137c729da68bb0b

logos: Don't print a blank line when process exits.

Before:
GSAFSJ1412D0117# echo testing | logos testfacility
GSAFSJ1412D0117# dmesg | grep testfacility
[ 2194.480329] testfacility: testing
[ 2194.480356] testfacility:
GSAFSJ1412D0117#

GSAFSJ1412D0117# echo -n | logos testfacility
GSAFSJ1412D0117# dmesg | grep testfacility
[12366.425968] testfacility:
GSAFSJ1412D0117#

After:
GSAFSJ1412D0117# echo testing | /tmp/logos testfacility
GSAFSJ1412D0117# dmesg | grep testfacility
[ 2211.275520] testfacility: testing
GSAFSJ1412D0117#

GSAFSJ1412D0117# echo -n | /tmp/logos testfacility
GSAFSJ1412D0117# dmesg | grep testfacility
GSAFSJ1412D0117#

Change-Id: Iae5aa6c141f2597454931f07b167a759e060f626

cmds/logos.c

diff --git a/cmds/logos.c b/cmds/logos.c
index 6c186a5..93577ce 100644
--- a/cmds/logos.c
+++ b/cmds/logos.c
@@ -642,7 +642,11 @@
     }
     got = read(0, buf + used, sizeof(buf) - used);
     if (got == 0) {
-      flush(header, headerlen, buf, used);
+      if (used > 0) {
+        /* Only output if there is text in the buffer, avoid
+         * printing a blank line when a process exits. */
+        flush(header, headerlen, buf, used);
+      }
       goto done;
     } else if (got < 0) {
       if (errno != EINTR && errno != EAGAIN) {