Alternative to R's `memory.size()` in linux?

Question

R\'s memory.size() is a Windows only. For other functions (such as windows()) the help page gives pointer to non-windows counterparts.

Answer 1

Using pryr library:

library("pryr")

mem_used()
# 27.9 MB

x <- mem_used()
x
# 27.9 MB
class(x)
# [1] "bytes"

Result is the same as @RHertel's answer, with pryr we can assign the result into a variable.

system('grep MemTotal /proc/meminfo')
# MemTotal:       263844272 kB

To assign to a variable with system call, use intern = TRUE:

x <- system('grep MemTotal /proc/meminfo', intern = TRUE)
x
# [1] "MemTotal:       263844272 kB"
class(x)
# [1] "character"