The R Project SVN R

Rev

Rev 42333 | Go to most recent revision | Details | Last modification | View Log | RSS feed

Rev Author Line No. Line
27442 ripley 1 
\name{read.socket}
2 
\title{ Read from or Write to a Socket}
3 
\usage{
4 
read.socket(socket, maxlen=256, loop=FALSE)
5 
write.socket(socket, string)
6 
}
7 
\alias{read.socket}
8 
\alias{write.socket}
9 
\arguments{
10 
    \item{socket}{a socket object}
11 
    \item{maxlen}{maximum length of string to read}
12 
    \item{loop}{wait for ever if there is nothing to read?}
13 
    \item{string}{string to write to socket}
14 
}
15 
\description{
16 
    \code{read.socket} reads a string from the specified socket,
17 
    \code{write.socket} writes to the specified socket.  There is very
18 
    little error checking done by either.
19 
}
20 
\value{
21 
    \code{read.socket} returns the string read.
22 
}
23 
\author{Thomas Lumley}
24 
 
25 
\seealso{
26 
    \code{\link{close.socket}}, \code{\link{make.socket}}
27 
}
28 
 
29 
\examples{
30 
finger <- function(user, host = "localhost", port = 79, print = TRUE)
31 
{
32 
    if (!is.character(user))
33 
        stop("user name must be a string")
34 
    user <- paste(user,"\r\n")
35 
    socket <- make.socket(host, port)
36 
    on.exit(close.socket(socket))
37 
    write.socket(socket, user)
38 
    output <- character(0)
39 
    repeat{
40 
        ss <- read.socket(socket)
41 
        if (ss == "") break
42 
        output <- paste(output, ss)
43 
    }
44 
    close.socket(socket)
45 
    if (print) cat(output)
46 
    invisible(output)
47 
}
48 
\dontrun{finger("root")  ## only works if your site provides a finger daemon}
49 
}
50 
\keyword{misc}