Rscript: Determine path of the executing script

Question

I have a script called foo.R that includes another script other.R, which is in the same directory:

#!/usr/bin/env Rscript
print("Hello")
source("other.R")

But I want R to find that other.R no matter what the current working directory.

In other words, foo.R needs to know its own path. How can I do that?

Answer 1

99% of the cases you might simply use:

sys.calls()[[1]] [[2]]

It will not work for crazy calls where the script is not the first argument, i.e., source(some args, file="myscript"). Use @hadley's in these fancy cases.

Answer 2

You can use the commandArgs function to get all the options that were passed by Rscript to the actual R interpreter and search them for --file=. If your script was launched from the path or if it was launched with a full path, the script.name below will start with a '/'. Otherwise, it must be relative to the cwd and you can concat the two paths to get the full path.

Edit: it sounds like you'd only need the script.name above and to strip off the final component of the path. I've removed the unneeded cwd() sample and cleaned up the main script and posted my other.R. Just save off this script and the other.R script into the same directory, chmod +x them, and run the main script.

main.R:

#!/usr/bin/env Rscript
initial.options <- commandArgs(trailingOnly = FALSE)
file.arg.name <- "--file="
script.name <- sub(file.arg.name, "", initial.options[grep(file.arg.name, initial.options)])
script.basename <- dirname(script.name)
other.name <- file.path(script.basename, "other.R")
print(paste("Sourcing",other.name,"from",script.name))
source(other.name)

other.R:

print("hello")

output:

burner@firefighter:~$ main.R
[1] "Sourcing /home/burner/bin/other.R from /home/burner/bin/main.R"
[1] "hello"
burner@firefighter:~$ bin/main.R
[1] "Sourcing bin/other.R from bin/main.R"
[1] "hello"
burner@firefighter:~$ cd bin
burner@firefighter:~/bin$ main.R
[1] "Sourcing ./other.R from ./main.R"
[1] "hello"

This is what I believe dehmann is looking for.

Answer 3

A slimmed down variant of Supressingfire's answer:

source_local <- function(fname){
    argv <- commandArgs(trailingOnly = FALSE)
    base_dir <- dirname(substring(argv[grep("--file=", argv)], 8))
    source(paste(base_dir, fname, sep="/"))
}

Answer 4

#!/usr/bin/env Rscript
print("Hello")

# sad workaround but works :(
programDir <- dirname(sys.frame(1)$ofile)
source(paste(programDir,"other.R",sep='/'))
source(paste(programDir,"other-than-other.R",sep='/'))

Answer 5

See findSourceTraceback() of the R.utils package, which

Finds all 'srcfile' objects generated by source() in all call frames. This makes it possible to find out which files are currently scripted by source().

Answer 6

I had issues with the implementations above as my script is operated from a symlinked directory, or at least that's why I think the above solutions didn't work for me. Along the lines of @ennuikiller's answer, I wrapped my Rscript in bash. I set the path variable using pwd -P, which resolves symlinked directory structures. Then pass the path into the Rscript.

Bash.sh

#!/bin/bash

# set path variable
path=`pwd -P`

#Run Rscript with path argument
Rscript foo.R $path

foo.R

args <- commandArgs(trailingOnly=TRUE)
setwd(args[1])
source(other.R)