The procbuf class is a GNU extension. It is derived from
streambuf. A procbuf can be closed (in which case
it does nothing), or open (in which case it allows communicating
through a pipe with some other program).
Constructor: procbuf::procbuf ()
Creates a procbuf in a closed state.
Method: procbuf* procbuf::open (const char *command, int mode)
Uses the shell (`/bin/sh') to run a program specified by command.
If mode is `ios::in', standard output from the program is sent
to a pipe; you can read from the pipe by reading from the
procbuf. (This is similar to `popen(command, "r")'.)
If mode is `ios::out', output written written to the
procbuf is written to a pipe; the program is set up to read its
standard input from (the other end of) the pipe. (This is similar to
`popen(command, "w")'.)
The procbuf must start out in the closed state.
Returns `*this' on success, and `NULL' on failure.
Constructor: procbuf::procbuf (const char *command, int mode)
Calls `procbuf::open (command, mode)'.
Method: procbuf* procbuf::close ()
Waits for the program to finish executing, and then cleans up the resources used. Returns `*this' on success, and `NULL' on failure.
Destructor: procbuf::~procbuf ()
Calls `procbuf::close'.