freebsd-ports/misc/cstream/pkg-descr

cstream is a general-purpose stream-handling tool like UNIX' dd,
usually used in commandline-constructed pipes.

- Sane commandline switch syntax.
- Exact throughput limiting, on the incoming side.
- Precise throughput reporting. Either at the end of the
  transmission or everytime SIGUSR1 is received. Quite useful to ask
  lengthy operations how much data has been transferred yet, i.e. when
  writing tapes. Reports are done in bytes/sec and if appropriate in
  KB/sec or MB/sec, where 1K = 1024.
- SIGHUP causes a clean shutdown before EOF on input.
- Build-in support to write its PID to a file.
- Build-in support for fifos. Example usage is a 'pseudo-device',
  something that sinks or delivers data at an appropriate rate, but
  looks like a file, i.e. if you test soundcard software.
- Built-in data creation and sink, no more redirection of
  /dev/null and /dev/zero. These special devices speed varies greatly
  among operating systems, redirecting from it isn't appropriate
  benchmarking and a waste of resources anyway.
-  "gcc -Wall" clean source code, serious effort taken to avoid
  undefined behavior in ANSI C or POSIX, except long long
  is required. Limiting and reporting works on data amounts > 4 GB.

WWW: http://www.cons.org/cracauer/cstream.html