similar to: R gets slow

Hello, I tried to code a R socket server but I did not succeed. The problem is that once the R socket server is created, I call the readLines function and then R gets blocked. The client seems to work fine since I tested it with a PERL server. I tried many combination of params in the socketConnection but none of them worked. I have seen some examples where the server sends something to a client

Hello, >From the doc, it says: "isOpen returns a logical value, whether the connection is currently open." But actually it seems to die on closed connections: > con <- file() > isOpen(con) [1] TRUE > close(con) > isOpen(con) Error in isOpen(con) : invalid connection Is it expected ? Tested on R-3.0.2 and R version 3.1.0 Patched (2014-06-11 r65921) on linux x86_64

I noticed the following file descriptor leak when I couldn't remove a package unless I shut down the R session that had loaded and used it. The function that triggered the problem printed the output of a call to parse(). Each time one prints a srcref a connection is opened and not closed. It looks like it happens in as.character.srcref's call to getSrcLines, which has some logic I

I am trying to create a Graphical User Interface for a Vorbis Player under MS Visual C++ 6.0 I was initially trting to use the code from decoder_example.c but I keep getting linker errors. I have set up my project as told to by James Boer on this mailing list. This is as follows: This document was prepared from an email received from James Boer on the Ogg Vorbis mailing list. It gives a

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

Hi! I'm wondering if there's a smart way around this: fileName= (some valid file on your system) > fileCon=file(fileName, open="rt") > l<-readLines (fileCon, n= 1) > > isOpen(fileCon) [1] TRUE > close(fileCon) > isOpen(fileCon) Error in isOpen(fileCon) : invalid connection How do you test for a file being closed if isOpen gives you an error

Dear all, I do not completely understand following behaviour : > con <- file("test.txt") > isOpen(con) [1] FALSE > open(con) > isOpen(con) [1] TRUE > close(con) > isOpen(con) Error in isOpen(con) : invalid connection > str(con) Classes 'file', 'connection' atomic [1:1] 3 ..- attr(*, "conn_id")=<externalptr> Why do I get an

> # creating a file > cat("sddfasdf", file="tempfile") > showConnections() class description mode text isopen can read can write > con <- file("tempfile", "r") > readLines(con) [1] "sddfasdf" Warning message: incomplete final line in: readLines(con, n, ok) > showConnections() class description mode text isopen

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) >

I'm been doing more and more of file text parsing inside R instead of coping with Perl. For that, I need open a file and read it line-by-line. I found the documentation for 'open' isn't very clear. Right now it has ,----[ *help(R)[open]* ] | 'open' opens a connection. In general functions using connections | will open them if they are not open, but then close them

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 connection was opened by readLines() internally, I don't necessarily know which one it is. E.g. I might open multiple

Thought I'd try and start a discussion. Feel free to jump in. I guess R needs to strike the right balance between opening up the internals to package writers and not allowing them to do bad things. My first attempt at cracking this nut is to just memcpy() the Rconnection and not allow access to the private stuff: /* Alternative to allowing C code access to connection API. */ Rconnection

Using dup() before fdopen() (and calling fclose() on the connection when it is closed) indeed fixes the memory leak. FYI, Gabor Index: src/main/connections.c =================================================================== --- src/main/connections.c (revision 71653) +++ src/main/connections.c (working copy) @@ -576,7 +576,7 @@ fp = R_fopen(name, con->mode); } else { /* use

Hi all, I am trying to create a function that will open connections to all files of one type within the working directory. I've got the function to open the connections, but I am having a bugger of a time trying to get these connections named as objects in the workspace. I am at the point where I can do it outside of the function, but not inside, using assign. I'm sure I'm

Consider this code. This is R 3.4.2, but based on a quick look at the NEWS, this has not been fixed. tryCatch( readLines(tempfile(), warn = FALSE)[1], error = function(e) NA, warning = function(w) NA ) rm(list=ls(all.names = TRUE)) gc() showConnections(all = TRUE) If you run it, you'll get a connection you cannot close(), i.e. the last showConnections() call prints: ?

Thanks for tracking this down. Yeah, I should use suppressWarnings(), you are right. Although, readLines() might throw another warning, e.g. for incomplete last lines, and you don't necessarily want to suppress that. TBH I am not sure why that warning is given: ? con <- file(tempfile()) ? open(con) Error in open.connection(con) : cannot open the connection In addition: Warning message: In

Hello yet again, R People: I was working with Ryacas and yacas last night and all was well. Now this morning, I keep getting the following: > a <- Sym("a") > a Error in summary.connection(x) : invalid connection > When I go to yacas from the command line, it works fine. Any suggestions, please? I'm thinking that a port might be open, but here I have: >

Hello, I am trying to create directories with R. I would like R to create directories because it is platform independent. I tried using file() and searching in "R Data Import/Export" but I did not succeed. I think it must be some function since exists the unlink to remove directories (and files). Pau

Hi, I am making multiple calls to gzfile() via read.table(), e.g. > x <- read.table( gzfile( "xxx.gz" ) ) After i do this many times (I haven't counted, but probably between 50 and 100 times) I get the error message: Error in open.connection(file, "r") : unable to open connection In addition: Warning message: cannot open compressed file 'xxx.gz' however, I

Hi Is there a way to detect that the process that corresponds to a pipe has ended? On my system (Ubuntu 13.04), I see > p <- pipe("true", "w"); Sys.sleep(1); system("ps -elf | grep true | grep -v grep"); isOpen(p) [1] TRUE The "true" process has long ended (as the filtered ps system call emits no output), still R believes that the pipe p is