store output of system command into a variable in r

Question

I am executing the following command in R :

system("ls ")

I need to store the output of the above command in some R variable. Is there a way to do the same??

johannes · Accepted Answer · 2016-06-15T15:01:51.093

145

Use intern=TRUE:

a <- system("ls ", intern = TRUE)

edited Jun 15 '16 at 15:01

answered Jun 19 '12 at 09:39

johannes

Is there a way to store the information if one makes a system call to a program? – Esben Eickhardt Dec 04 '18 at 14:44
Is there any way to get both the os program status code and the output of the program? – ichbinallen Dec 11 '18 at 20:26
1

What if I am shelling out to an SQL command which returns 1 million rows? How can I redirect the output to a file first? – Leonid Mar 22 '19 at 23:17

score 8 · Answer 2 · answered Jun 19 '12 at 09:53

8

why not use the corresponding R function?

a <- list.files()
b <- list.files(recursive = TRUE)

For more details

?list.files

answered Jun 19 '12 at 09:53

Thierry

1

Because `list.files` also lists directories as items, and if you use `recursive=T` it dives into those directories. There is no simple R way to list _just the files_ in a directory. I use `file_list = system('ls -p | grep -v /')` – abalter Mar 11 '19 at 01:37

2 Answers2