similar to: Discussion starter for package level Connection API

Here's an update of my rawConnection() implementation. In addition to providing a raw version of textConnection(), this fixes two existing issues with textConnection(): one is that the current textConnection() implementation carries around unprotected SEXP pointers, the other is a performance problem due to prolific copying of the output buffer as output is accumulated line by line. This new

When I originally implemented connections in R 1.2.0, I followed the model in the 'Green Book' closely. There were a number of features that forced a particular implementation, and one was getConnection() that allows one to recreate a connection object from a number. I am wondering if anyone makes use of this, and if so for what? It would seem closer to the R philosophy to have

Hello, I'm trying to use the limited connections api defined in Rinternals.h. I have code that looks like this (inspired from do_serializeToConn) : SEXP serialize_to_connection( SEXP xp, SEXP connection ){ Rconnection con ; struct R_outpstream_st out; R_pstream_format_t type = R_pstream_binary_format ; SEXP (*hook)(SEXP, SEXP) = NULL ; con = getConnection(Rf_asInteger(connection));

Hello all, I would like to request that getConnection() and the struct Rconn declarations be added to the R embedded interface. Here's why. It's common in CGI scripts for web applications to direct stdin, stdout, and stderr map to reading from the browser, writing to the browser, and writing to a web log file respectively; very nice and neat. However, things get a little hairy once

I've just implemented a generalization of R's text connections, to also support reading/writing raw binary data. There is very little new code to speak of. For input connections, I wrote code to populate the old text connection buffer from a raw vector, and provided a new raw_read() method. For output connections, I wrote a raw_write() to append to a raw vector. On input, the mode

Dear all, I hope somebody can help me understand if package authors are allowed to create custom R connections or not. Until today, I thought that R had an "official" way to define custom connections. E.g. this is an old commit message that was supposed to create an API, maybe internal, though. > r62016 | urbaneks | 2013-02-21 14:29:44 -0500 (Thu, 21 Feb 2013) | 1 line > add API

As far as I can tell, 'isOpen' cannot return FALSE in the case when 'rw = ""'. If the connection has already been closed by 'close' or some other function, then isOpen will produce an error. The problem is that when isOpen calls 'getConnection', the connection cannot be found and 'getConnection' produces an error. The check to see if it is

Hello R developers, I am working on the "seqinr" package and I encounter a tricky problem using a C function. We defined a C fonction called "getzlibsock" which is dedicated to compressed socket connections. This function is using the R internal C function called "getConnection(int)" in order to get information about the socket previously opened with the

Hi all, I've been writing a package and I've run into a problem that I'm unsure how to solve. I am looking to pass a C++ class object to R so that it may be passed back to another C++ function later on to be used. I'm quite new to R and this is my first time writing a package, so I hope you can bear with me. The following is how I create the class and use

Gabor, You can grab the connection and destroy it via getConnection and then a standard close call. (it actually lists that it is "closed" already, but still in the set of existing connections. I can't speak to that difference). > tryCatch( + readLines(tempfile(), warn = FALSE)[1], + error = function(e) NA, + warning = function(w) NA + ) [1] NA >

While using the file functions have found a few more issues (on both Unix and Windows) ie R documentation: In the "close" description (base package) we see that the possible values for the mode 'open' the "r+" and "r+b" values are repeated, and are incorrect the second time. The second set actually corresponds to the "w+" / "w+b", see

SUMMARY: I'm proposing that R assert that 'connection' options have not changed since first created such that R will produce the following error: > fh <- file("a.txt", open = "w+") > cat("hello\n", file = fh) > close(fh) > fh2 <- file("b.txt", open = "w+") > cat("world\n", file = fh2) >

On Thu, Dec 14, 2017 at 12:17 PM, G?bor Cs?rdi <csardi.gabor at gmail.com> wrote: > On Thu, Dec 14, 2017 at 7:56 PM, Gabriel Becker <gmbecker at ucdavis.edu> > wrote: > > Gabor, > > > > You can grab the connection and destroy it via getConnection and then a > > standard close call. > > Yeah, that's often a possible workaround, but since this

Hi all, first of all: Sorry for my bad englis, and now the Question: I have some problems with running R from Java. First i tried using rJava (JRI). But the examples didnt work properly. Now im trying to establish a connection by using Rserve and JRclient (RF503). I have the following code, which i`ve found: ------------------------------------------------------------------------ public

I was wondering if there was a function like "does connection exists" ? I am currently using loops to build up a database, and I have either > B = getConnection(localization) Error in getConnection(localization) : there is no connection -2147483648 In addition: Warning message: In getConnection(localization) : NAs introduced by coercion or > B = scan(localization) Error in

This has nothing to do with on.exit. It is an iteraction between where the warning is signaled in 'file' and your _exiting_ warning handler. This combination has the same issue, tryCatch(file(tempfile(), "r"), warning = identity) showConnections(all = TRUE) as does options(warn=2) file(tempfile(), "r") showConnections(all = TRUE) I haven't looked at the

Hi, I am facing one problem of fetching R warning messages in Java Code using Rserve. It is easier to trap R Error messages by using catching RSrvException. I came to know one way of fetching R Warning messages, i.e. using "withCallingHandlers", below is my Java Program, which uses withCallingHandlers of R : import org.rosuda.JRclient.*;

The patch below adds support for custom HTTP headers in download.file() and url(). My main motivation for this is performing basic http authentication. Some web sites do not support embedding the credentials into the URI itself, they only work if the username and password are sent in the HTTP headers. In fact specifying the username and password in the URI has been

Hi. I nearly have Rserve working.... I have the dialog box which says.. Rserve: Ok, read to answer queries. Having read all i can find, I followed the guidance given on http://rosuda.org/Rserve/example.shtml I tried to follow the first example but I am getting an error descirbed below. My IDE looks like this: http://www.nabble.com/file/p10705244/ide.jpg However, when I try and compile my

I have been experiencing issues with an R script hanging when connecting to an Oracle database. To help debug, I found a function here in the nabble forum and made a small test script: #!/usr/bin/Rscript --no-restore --no-save --no-init-file library("RJDBC") drv<-JDBC("oracle.jdbc.OracleDriver","/home/oracle/lib/ojdbc6.jar", "'") dbCheck =