Displaying 20 results from an estimated 3000 matches similar to: "getting corrupted data when using readBin() after seek() on a gzfile connection"
2007 Dec 31
1
readBin differences on Windows and Linux/mac
I have been trying to use the gunzip function in the R.utils package. It
opens a connection to a gzfile, uses readBin to read from that connection,
and then uses writeBin to write out the raw data to a new file. This works
as expected under linux/mac, but under Windows, I get:
Error in readBin(inn, what= raw(0), size = 1, n=BFR.SIZE) :
negative length vectors are not allowed
A simple
2008 Apr 28
4
R 2.7.0, match() and strings containing \0 - bug?
Hi,
A piece of my code that uses readBin() to read a certain file type is
behaving strangely with R 2.7.0. This seems to be because of a failure
to match() strings after using rawToChar() when the original was
terminated with a "\0" character. Direct equality testing with ==
still works as expected. I can reproduce this as follows:
> x <- "foo"
> y <-
2001 Dec 11
1
Using lib Rstreams and gzfile()
Hi all,
in the last time I've intensively used Rstreams to read and write from
binary files. Now I'm wondering if it is possible to use Rsteams
functions with gzipped files. But I haven't found the trick:
> p1c.gzip <- gzfile("daten/p1c_all.mea.gz", open="rb")
> readBin(p1c.gzip, integer(), n=64,size=2)
[1] 84 1 400 1 749 0 0 0
2006 Nov 14
2
gzfile with multiple entries in the archive
If I open a tgz archive with gzfile and then parse it using readLines I miss
the initial line of each member of the archive - and also the name of the
file although the archive otherwise complete (but useless!).
Is there any way within R to extract both the list of files in a tgz archive
and to extract any one of these files?
Clearly I can use zcat and tar on Linux, but I need this to work
2013 Apr 10
1
Issue with Control-Z in a text file on Windows - readLines() appears to truncate
Working on Windows I have had to deal with CSV files that,
unfortunately, contain embedded Control-Zs, i.e. ASCII character 26 in
decimal, and the readLines() function in R on Windows (2.15.2 and
3.0.0) appears to truncate at the control-Z. There is no problem at
all on Ubuntu Linux with R 3.0.0.
Am I mistaken or is this genuine?
# Create a small file with embedded Control-Z
h3 <-
2002 Aug 05
1
pipe and binary i/o
I often want to use "pipe" with "readBin" to read (binary) data from the
standard output of a Perl or C program. For that I need "pipe" to work with
the "open='rb'" option. It never worked for me, and after a look at the
connections.c file, I see that in "pipe_open" the mode gets passed directly
to "popen" (I'm using Linux on
2020 Jun 29
0
A warning in gzcon but not in gzfile
Hi all,
I used `gzfile` and `gzcon` to read a compressed file but I found that
`gzcon` gave me a different result than `gzfile`. It seems like the `gzcon`
does not handle the data correctly. I have posted an example below. In the
example, a portion of a compressed file is downloaded from Google Cloud as
a raw vector, and the data is saved into a temp file. If I use ` gzfile` to
read the file, it
2002 Dec 05
1
writing to gzfile: segmentation fault (PR#2347)
Full_Name: Vadim Ogranovich
Version: Version 1.6.0 (2002-10-01)
OS: Red Hat 7.1
Submission from: (NULL) (209.99.241.1)
The following sequence of commands crashes my R session. The first weirdness
happens after the second command that appears not to change the "foo.gz" file,
no error generated.
> con <- gzfile("foo.gz", open="w"); cat("goo\n",
2006 Oct 21
2
Possible bugs in 'seek' and 'readBin'
I found that
seek(..., origin = 'current', ...)
and
readBin(..., what = 'integer', ...)
or 'int'
do not work correctly.
Did anyone have the same experience?
2006 Jun 28
2
read file with readBin (the file was saved with a C-routine)
Hello!
I have problems with using of "readBin" to read files, which was written in C with "fwrite". In the C-File there is the following Code:
fwrite(MyitINI,sizeof(itINItype),1,outfile);
where MyitINI is a structure of the following form
typedef struct{
int KernelFileSave; /* Determined, if Systemmatrix saved or not.*/
char KernelFileName[200]; /* A-Matrix name
2008 Feb 28
2
compress data on read, decompress on write
Dear All,
I'd like to be able to have R store (in a list component) a compressed
data set, and then write it out uncompressed. gzcon and gzfile work in
exactly the opposite direction. What would be a good way to handle
this?
Details:
----------
We have a package that uses C; part of the C output is a large sparse
matrix. This is never manipulated directly by R, but always by the C
code.
2009 May 18
2
readBin on binary non-blocking connections (Windows & Unix differences/bugs)
R-devel:
I am encountering a consistency issue using socketConnection and
readBin with *non-blocking* connections on Unix and Windows XP (no
Vista to test).
I am a bit confused by the behavior of *non-blocking* connections
under Windows specifically. When calling readBin on a non-blocking
connection when there is no data to read on the socket, the connection
under Unix will return a vector of
2007 Jan 26
1
readBin is much slower for raw input than for a file
Dear all,
I'm trying to write an efficient binary file reader for a file type
that is made up of several fields of variable length, and so requires
many small reads. Doing this on the file directly using a sequence of
readBin() calls is a bit too slow for my needs, so I tried buffering
the file into a raw vector and reading from that ("loc" is the
equivalent of the file pointer):
2007 Jan 26
1
readBin is much slower for raw input than for a file
Dear all,
I'm trying to write an efficient binary file reader for a file type
that is made up of several fields of variable length, and so requires
many small reads. Doing this on the file directly using a sequence of
readBin() calls is a bit too slow for my needs, so I tried buffering
the file into a raw vector and reading from that ("loc" is the
equivalent of the file pointer):
2007 Jul 03
1
bug in closing gzfile-opened connections?
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
2006 Sep 27
2
Single Precision (4 byte) floats with readBin
I would like to use readBin to read a binary data
file. Most of the data is 4-byte floating point but,
for some reason, only double precision appears to be
offered. I tried
fVariable=readBin(iFile,what=single());
and got 35.87879 which looks believable except that
the correct value is 3.030303. I then tried
fVariable=readBin(iFile,what=single(),4);
and got
[1] 3.831111e+10 6.657199e+10
2019 Nov 18
2
readBin should check that its endian argument is a legal value
I think it would be helpful if readBin checked that its endian argument is
a legal value.
Why? I was reviewing some of our code and noticed that the author had
readBin(..., endian="network") and never having heard of "network", I
looked at the man page for readBin, and it hadn't heard of "network"
either. Not good.
I then looked at the R code for readBin, which
2006 Jun 02
1
Typo fix for readBin.Rd
Hi,
The man page for readBin has a small typo:
--- a/src/library/base/man/readBin.Rd
+++ b/src/library/base/man/readBin.Rd
@@ -58,7 +58,7 @@ writeBin(object, con, size = NA, endian
\code{readBin} and \code{writeBin} read and write C-style
zero-terminated character strings. Input strings are limited to 10000
- characters. \code{\link{readChar}} and \code{\code{writeChar}}
+
2018 May 10
2
readLines() behaves differently for gzfile connection
When I read a .gz file with readLines() in 3.4.3, it returns text (and a
warning). In 3.5.0, it gives a warning, but no text. Is this expected
behavior or a bug?
3.4.3:
> source_file = "1k_annotation.gz"
> readfile_con <- gzfile(source_file, "r")
> readLines(readfile_con, n = 5)
[1] "#chr\tpos\tref\talt\t
<truncated output here>
Warning message:
In
2002 Mar 05
3
reading 2-byte integers using readBin and connections
Hi folks:
This may be a stupid question, but I cannot seem to find a way to tell
readBin that I want to read 2-byte integers from the connection. The input
file is 150,720 bytes long containing 75,360 short (2-byte) integers. But
specifying "integer" or "int" for what in readBin only returns me a vector
of length 37680, leading me to believe that sizeof(integer) or