shithub: riscv

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added aux/seek

--- a/sys/src/cmd/aux/mkfile

+++ b/sys/src/cmd/aux/mkfile

@@ -31,6 +31,7 @@

 	rdwr\

 	reboot\

 	searchfs\

+	seek\

 	statusbar\

 	stub\

 	tablet\

--- /dev/null

+++ b/sys/src/cmd/aux/seek.c

@@ -1,0 +1,33 @@

+#include <u.h>

+#include <libc.h>

+

+void

+main(int argc, char **argv)

+{

+	char buf[512];

+	vlong size;

+	vlong pos;

+	vlong ns;

+	int fd;

+	int i;

+

+	if(argc != 2) {

+		fprint(2, "usage: %s /dev/sd??/data\n", argv[0]);

+		exits("usage");

+	}

+	

+	srand(time(0));

+	fd = open(argv[1], OREAD);

+	if(fd < 0)

+		sysfatal("open: %r");

+	size = seek(fd, 0, 2) / 512;

+	ns = nsec();

+	for(i=0;i<100;i++) {

+		pos = (vlong)(frand() * size);

+		if(pread(fd, buf, 512, 512 * pos) < 512)

+			sysfatal("read: %r");

+	}

+	ns = nsec() - ns;

+	print("%.3g\n", ((double)ns)/100000000);

+	exits(nil);

+}