similar to: cannot destroy connection (?) created by readLines in a tryCatch

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

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

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 >

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

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

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

This may be more of an OS question ... I have this call r = get.hist.quote(symbol, start= format(start, "%Y-%m-%d"), end= format(end, "%Y-%m-%d")) which does a url request in a loop and my program runs out of file handlers after few hundred rotations. The error message is: 'Too many open files'. Other than increasing the file handlers assigned to my process, is there

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 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

Cran task views seems to be a "once-per-session" process -- the first attempt to access views in a (RGui for Windows) session works, but subsequent attempts fail. There is a noticeably long pause before the failing call returns. Example session with two calls to "available.views" follows, but similar effects have been observed with two calls to "install.views" and

> # 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

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: >

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

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

I'm trying to figure out how to get out of this situation: > source('monit.r') Error in file(file, "r") : All connections are in use > showConnections() description class mode text isopen can read can write > help.search('connection') Error in file(file, "r") : All connections are in use > q() Save workspace image? [y/n/c]: y Error

When I use sink(filename) to save the results of the run, the file does not seem to be closed or released back to the OS after I issue the "sink()" command. Here is a baby example: sink("test.txt") tdta <- data.frame(x = x <- 0:10,y = 2 * x + rnorm(11)) print(summary(lm(y ~ x, data=tdta))) sink() At this point (even after refreshing the Explorer window) the filesize

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 all, I'm writing a function that read data from a binary file. I want to close all opened connections, but it failed: > showConnections() description class mode text isopen can read can write 3 "daten/t5_all.mea" "file" "rb" "binary" "opened" "yes" "no" 4 "daten/t5_all.mea"

Hi all, I have newly discovered the power of connections (although just a small part of it, namely the file() connection). It allowed me to process data file with arbitrary number of fields per line, which I was using awk for preprocessing before readling into R. The combination of the connection, readLines() and strsplit() really make the work a lot easier and more organized. Thanks a bundle

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