by chiparus:

What steps will reproduce the problem?
If possible, include a link to a program on play.golang.org.

Let a program log to syslog. When you restart the syslog daemon, logging stops. This is
because the write() function does not pass the error (if any) from fmt.Fprintf() to the
caller. In fact, write() always returns nil so errors were never detected.

This little patch fixes it:

diff -r 45468e9eae1f src/pkg/log/syslog/syslog.go
--- a/src/pkg/log/syslog/syslog.go  Wed May 22 18:51:15 2013 +0800
+++ b/src/pkg/log/syslog/syslog.go  Wed May 22 14:57:31 2013 +0200
@@ -258,10 +258,9 @@
    }
 
    timestamp := time.Now().Format(time.RFC3339)
-   fmt.Fprintf(w.conn, "<%d>%s %s %s[%d]: %s%s",
+   return fmt.Fprintf(w.conn, "<%d>%s %s %s[%d]: %s%s",
        p, timestamp, w.hostname,
        w.tag, os.Getpid(), msg, nl)
-   return len(msg), nil
 }
 
 // NewLogger creates a log.Logger whose output is written to