similar to: connections: remember to close it!

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

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

I have several data input functions that include a construct like the following: indat <- function(stuff) { [...] awkp <- paste("awk ...yada yada...", stuff, etc.) scan(pipe(awkp),quiet=TRUE) } I use these functions a lot, and as I do, a lengthening list of closed, but undestroyed, connections accumulates. Ultimately this appears to stuff things up and cause

Full_Name: Henrik Bengtsson Version: R v1.4.0 OS: Solaris 8 Submission from: (NULL) (130.235.3.49) When I am trying the following on Rv1.4.0 on Solaris 8, I get that the "cannot close output sink connection": % R --vanilla tmpfile <- tempfile() # Create a filename that does not exist for(k in 1:100) { cat(k, ": "); try(fh <- file(tmpfile, "r"))

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

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) >

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

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 everyone, I'm an R newbie working with the poLCA module. I achieved my target without having to bother anyone, but It seems that I've got stuck at the last minute. My problem is simple. I need to write my results into a file. My results are in the shape of a list (unbalanced columns) I've considered several methods (sink(), write.file) etc. etc. Unfortunately, I'm not the best

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"

Hello, I'm having a problem in R with repeated use of the "load", "save", and "close" commands. I'm getting an error message that reads, "Too many open files". I'm opening files and closing them (and unlinking them), but when I go through that process 509 times, the program halts and I get this error message: "cannot open the

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: ?

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

On 17/07/2009 7:57 PM, Marilyn & Rich Short wrote: > Hello, > > I'm having a problem in R with repeated use of the "load", "save", and > "close" commands. I'm getting an error message that reads, "Too many > open files". I'm opening files and closing them (and unlinking them), > but when I go through that process 509

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

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

Hi, I suddenly started getting strange errors while working on my caTools package: >RCMD install C:/programs/R/rw2011/src/library/caTools ...... preparing package caTools for lazy loading Error in file(file, "r", encoding = encoding) : all connections are in use Execution halted make: *** [lazyload] Error 1 *** Installation of caTools failed *** I searched

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));

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

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 =