log/linux: make default output stderr

[ upstream commit 5988725 ]

In Linux by default DPDK log goes to stdout, as well as syslog.

It is possible for an application to change the library output stream
via 'rte_openlog_stream()' API, to set it to stderr, it can be used as:
rte_openlog_stream(stderr);

But still updating the default log output to 'stderr'.

Bugzilla ID: 8
Fixes: af75078 ("first public release")

Reported-by: Alexandre Ferrieux <alexandre.ferrieux@orange.com>
Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>

lib/librte_eal/linux/eal_log.c

@@ -27,9 +27,9 @@ console_log_write(__rte_unused void *c, const char *buf, size_t size)
 {
 	ssize_t ret;
 
-	/* write on stdout */
-	ret = fwrite(buf, 1, size, stdout);
-	fflush(stdout);
+	/* write on stderr */
+	ret = fwrite(buf, 1, size, stderr);
+	fflush(stderr);
 
 	/* Syslog error levels are from 0 to 7, so subtract 1 to convert */
 	syslog(rte_log_cur_msg_loglevel() - 1, "%.*s", (int)size, buf);