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-rw-r--r--sysdeps/unix/sysv/linux/getloadavg.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/getloadavg.c b/sysdeps/unix/sysv/linux/getloadavg.c
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index 0000000000..1612ad2e56
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/getloadavg.c
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+/* Get system load averages.  Linux (/proc/loadavg) version.
+   Copyright (C) 1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+
+/* Put the 1 minute, 5 minute and 15 minute load averages
+   into the first NELEM elements of LOADAVG.
+   Return the number written (never more than 3, but may be less than NELEM),
+   or -1 if an error occurred.  */
+
+int
+getloadavg (double loadavg[], int nelem)
+{
+  int fd;
+
+  fd = __open ("/proc/loadavg", O_RDONLY);
+  if (fd < 0)
+    return -1;
+  else
+    {
+      char buf[65], *p;
+      ssize_t nread;
+      int i;
+
+      nread = __read (fd, buf, sizeof buf - 1);
+      close (fd);
+      if (nread < 0)
+	return -1;
+      buf[nread - 1] = '\0';
+
+      if (nelem > 3)
+	nelem = 3;
+      p = buf;
+      for (i = 0; i < nelem; ++i)
+	{
+	  char *endp;
+	  loadavg[i] = strtod (p, &endp);
+	  if (!endp || endp == p)
+	    break;
+	  p = endp;
+	}
+
+      return i;
+    }
+}