1 files changed, 52 insertions, 0 deletions
diff --git a/open_files.c b/open_files.c
new file mode 100644
index 0000000..3f82c8b
--- /dev/null
+++ b/open_files.c
@@ -0,0 +1,52 @@
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include "common.h"
+
+int open_files(int argc, char **argv) {
+	FILE *f;
+	int alloc, freeh, avail;
+	if(argc > 1) {
+		if(!strcmp(argv[1], "config")) {
+			if(!(f=fopen("/proc/sys/fs/file-nr", "r"))) {
+				fprintf(stderr, "cannot open /proc/sys/fs/file-nr\n");
+				return 1;
+			}
+			if(1 != fscanf(f, "%*d %*d %d", &avail)) {
+				fclose(f);
+				fprintf(stderr, "cannot read from /proc/sys/fs/file-nr\n");
+				return 1;
+			}
+			fclose(f);
+			puts("graph_title File table usage\n"
+				"graph_args --base 1000 -l 0\n"
+				"graph_vlabel number of open files\n"
+				"graph_category system\n"
+				"graph_info This graph monitors the Linux open files table.\n"
+				"used.label open files\n"
+				"used.info The number of currently open files.\n"
+				"max.label max open files\n"
+				"max.info The maximum supported number of open files. Tune by modifying /proc/sys/fs/file-max.");
+			printf("used.warning %d\nused.critical %d\n", (int)(avail*0.92), (int)(avail*0.98));
+			return 0;
+		}
+		if(!strcmp(argv[1], "autoconf")) {
+			if(0 == access("/proc/sys/fs/file-nr", R_OK))
+				return writeyes();
+			else
+				return writeno("/proc/sys/fs/file-nr not readable");
+		}
+	}
+	if(!(f=fopen("/proc/sys/fs/file-nr", "r"))) {
+		fputs("cannot open /proc/sys/fs/file-nr\n", stderr);
+		return 1;
+	}
+	if(3 != fscanf(f, "%d %d %d", &alloc, &freeh, &avail)) {
+		fclose(f);
+		fputs("cannot read from /proc/sys/fs/file-nr\n", stderr);
+		return 1;
+	}
+	fclose(f);
+	printf("used.value %d\nmax.value %d\n", alloc-freeh, avail);
+	return 0;
+}