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% File src/library/utils/man/read.socket.Rd
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% Part of the R package, https://www.R-project.org
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% Copyright 1995-2012 R Core Team
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% Distributed under GPL 2 or later
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\name{read.socket}
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\title{ Read from or Write to a Socket}
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\usage{
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read.socket(socket, maxlen = 256L, loop = FALSE)
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write.socket(socket, string)
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}
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\alias{read.socket}
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\alias{write.socket}
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\arguments{
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    \item{socket}{a socket object.}
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    \item{maxlen}{maximum length (in bytes) of string to read.}
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    \item{loop}{wait for ever if there is nothing to read?}
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    \item{string}{string to write to socket.}
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}
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\description{
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    \code{read.socket} reads a string from the specified socket,
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    \code{write.socket} writes to the specified socket.  There is very
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    little error checking done by either.
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}
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\value{
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  \code{read.socket} returns the string read as a length-one character vector.
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  \code{write.socket} returns the number of bytes written.
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}
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\author{Thomas Lumley}
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\seealso{
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    \code{\link{close.socket}}, \code{\link{make.socket}}
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}
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\examples{
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finger <- function(user, host = "localhost", port = 79, print = TRUE)
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{
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    if (!is.character(user))
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        stop("user name must be a string")
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    user <- paste(user,"\r\n")
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    socket <- make.socket(host, port)
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    on.exit(close.socket(socket))
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    write.socket(socket, user)
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    output <- character(0)
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    repeat{
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        ss <- read.socket(socket)
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        if (ss == "") break
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        output <- paste(output, ss)
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    }
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    close.socket(socket)
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    if (print) cat(output)
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    invisible(output)
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}
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\dontrun{
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finger("root")  ## only works if your site provides a finger daemon}
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}
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\keyword{misc}