diff options
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | ext/io/wait/wait.c | 26 |
2 files changed, 31 insertions, 0 deletions
@@ -1,3 +1,8 @@ +Mon Dec 29 18:02:45 2008 Yukihiro Matsumoto <matz@ruby-lang.org> + + * ext/io/wait/wait.c (io_nread): returns number of bytes available + for read. response to feature request #936 in [ruby-core:20917]. + Mon Dec 29 17:52:16 2008 Yukihiro Matsumoto <matz@ruby-lang.org> * ext/io/wait/wait.c (io_ready_p): updated to follow RDoc. diff --git a/ext/io/wait/wait.c b/ext/io/wait/wait.c index 24e4141162..b73c9af1ce 100644 --- a/ext/io/wait/wait.c +++ b/ext/io/wait/wait.c @@ -44,6 +44,31 @@ EXTERN struct timeval rb_time_interval _((VALUE time)); /* * call-seq: + * io.nread -> int + * + * Returns number of bytes that can be read without blocking. + * Returns zero if no information available. + */ + +static VALUE +io_nread(VALUE io) +{ + rb_io_t *fptr; + int len; + ioctl_arg n; + + GetOpenFile(io, fptr); + rb_io_check_readable(fptr); + len = rb_io_read_pending(fptr); + if (len > 0) return len; + if (!FIONREAD_POSSIBLE_P(fptr->fd)) return INT2FIX(0); + if (ioctl(fptr->fd, FIONREAD, &n)) return INT2FIX(0); + if (n > 0) return ioctl_arg2num(n); + return INT2FIX(0); +} + +/* + * call-seq: * io.ready? -> true, false or nil * * Returns true if input available without blocking, or false. @@ -137,6 +162,7 @@ io_wait(int argc, VALUE *argv, VALUE io) void Init_wait() { + rb_define_method(rb_cIO, "nread", io_nread, 0); rb_define_method(rb_cIO, "ready?", io_ready_p, 0); rb_define_method(rb_cIO, "wait", io_wait, -1); } |