[R] bugs in system() handling long character strings??

[ripley@stats.ox.ac.uk]

There is an undocumented limit of 119 characters/line when using
system(intern=TRUE) on Unix.  You can easily raise it: it is in
do_system in file src/unix/sys-unix.c.

I think this limit should be raised considerably, but it may well not be
worth eliminating it.

On Sat, 7 Dec 2002, Naoki Takebayashi wrote:

> Hi,
>
> system(cmd, intern=T) seems to have a problem when cmd returns a long
> character string.
>
> For example, if a file (/tmp/long.txt) contains a long string such as:
>
> 123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
>
> There are 120 characters in this one line.
>
> > junk <- system("cat /tmp/long", TRUE)
> > junk
> [1] "1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678"
> [2] "0"
> > nchar(junk[1])
> [1] 118
>
> So one long line get separated into two parts, and additionally 119-th
> character is missing.
>
> Is this a bug in R or am I missing something?
>
> I tried this on R-1.6.1 on linux/alpha and linux/i386.
>
> Thanks,
> Naoki
>
> Naoki Takebayashi     <ntakebay at bio.indiana.edu>
> --- Dept. of Biology, Box 90338, Duke University, Durham, NC 27708-0338
>
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-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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