Add a note about /dev/urandom to README.md

1 files changed, 1 insertions, 0 deletions

diff --git a/README.md b/README.md
index 06720791f..f5e833fca 100644
--- a/README.md
+++ b/README.md
@@ -21,3 +21,4 @@ Then just `make`.
  - Some crufty old Windows code (Windows XP, cmd.exe) doesn't like forward slashes in environment variables.  The -X shell option (which must be the first argument) prevents busybox-w32 from changing backslashes to forward slashes.  If Windows programs don't run from the shell it's worth trying it.
  - If you want to install 32-bit BusyBox in a system directory on a 64-bit version of Windows you should put it in `C:\Windows\SysWOW64`, not `C:\Windows\System32` as you might expect.  On 64-bit systems the latter is for 64-bit binaries.
  - ANSI escape sequences are emulated by converting to the equivalent in the Windows console API.  Setting the environment variable `BB_SKIP_ANSI_EMULATION` will cause ANSI escapes to be passed to the console without emulation.  This may be useful for Windows consoles that support ANSI escapes (e.g. ConEmu).
+ - It's possible to obtain pseudo-random numbers using `if=/dev/urandom` as the input file to `dd`.  The same emulation of `/dev/urandom` is used internally by the `shred` utility and to support https in `wget`.  Since the pseudo-random number generator isn't being seeded with sufficient entropy the randomness shouldn't be relied on for any serious use.