Of course they have separate criteria for determining existence... they do different things, and therefore have different requirements for access permissions. -- Sent from my phone. Please excuse my brevity.
On January 13, 2017 3:54:35 AM PST, Benjamin Tyner <bty...@gmail.com> wrote: >Thank you for the insights, Rolf and Henrik. > >To give another example, this time in non-interactive mode, > > Rscript -e "file.exists(commandArgs(TRUE))" <(echo "Hi") > > [1] TRUE > >versus > > Rscript -e "normalizePath(commandArgs(TRUE))" <(echo "Hi") > [1] "/dev/fd/63" > Warning message: > In normalizePath(commandArgs(TRUE)) : > path[1]="/dev/fd/63": No such file or directory > >It almost seems like file.exists and normalizePath use separate >criteria >for determining existence? > >Regards > >Ben > >On 01/12/2017 01:42 AM, Rolf Turner wrote: >> On 12/01/17 16:33, Henrik Bengtsson wrote: >> >> <SNIP> >> >>> FYI, the /proc is there because Unix has something called the "proc >>> filesystem (procfs; https://en.wikipedia.org/wiki/Procfs) is a >special >>> filesystem in Unix-like operating systems that presents information >>> about processes and other system information in a hierarchical >>> file-like structure". For instance, you can query the uptime of the >>> machine by reading from /proc/uptime: >>> >>> $ cat /proc/uptime >>> 332826.96 661438.10 >>> >>> $ cat /proc/uptime >>> 332871.40 661568.50 >>> >>> >>> You can get all IDs (PIDs) of all processes currently running: >>> >>> $ ls /proc/ | grep -E '^[0-9]+$' >>> >>> and for each process you there are multiple attributes mapped as >>> files, e.g. if I start R as: >>> >>> $ R --args -e "message('hello there')" >>> >>> then I can query that process as: >>> >>> $ pid=$(pidof R) >>> $ echo $pid >>> 26323 >>> >>> $ cat /proc/26323/cmdline >>> /usr/lib/R/bin/exec/R--args-emessage('hello there') >>> >>> Unix is neat >> >> Indeed. Couldn't agree more. Thanks for the insight. >> >> <SNIP> >> >> cheers, >> >> Rolf >> > >______________________________________________ >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >https://stat.ethz.ch/mailman/listinfo/r-help >PLEASE do read the posting guide >http://www.R-project.org/posting-guide.html >and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.