close_write()
public
Closes the write end of a duplex I/O stream
(i.e., one that contains both a read and a write stream, such as a pipe). Will raise an IOError if the stream is not duplexed.
f = IO.popen("/bin/sh","r+")
f.close_write
f.print "nowhere"
produces:
prog.rb:3:in `write': not opened for writing (IOError)
from prog.rb:3:in `print'
from prog.rb:3
Show source
static VALUE
rb_io_close_write(VALUE io)
{
rb_io_t *fptr;
VALUE write_io;
if (rb_safe_level() >= 4 && !OBJ_UNTRUSTED(io)) {
rb_raise(rb_eSecurityError, "Insecure: can't close");
}
write_io = GetWriteIO(io);
GetOpenFile(write_io, fptr);
if (is_socket(fptr->fd, fptr->pathv)) {
if (shutdown(fptr->fd, SHUT_WR) < 0)
rb_sys_fail_path(fptr->pathv);
fptr->mode &= ~FMODE_WRITABLE;
if (!(fptr->mode & FMODE_READABLE))
return rb_io_close(write_io);
return Qnil;
}
if (fptr->mode & FMODE_READABLE) {
rb_raise(rb_eIOError, "closing non-duplex IO for writing");
}
rb_io_close(write_io);
if (io != write_io) {
GetOpenFile(io, fptr);
fptr->tied_io_for_writing = 0;
fptr->mode &= ~FMODE_DUPLEX;
}
return Qnil;
}