Hello,

Below is the code leading to the error. It is basically copied from the example:

rm(list = ls())

library(rhdf5)

setwd('~/prg/git/test')

h5createFile("myhdf5file2.h5")
h5createGroup("myhdf5file2.h5","foo")
A = matrix(1:10,nr=5,nc=2)
h5write(A, file = "myhdf5file2.h5",name = "foo/A")

Error in on.exit(H5Sclose(h5spaceMem), add = TRUE, after = FALSE) :
  unused argument (after = FALSE)

The argument after was only added to on.exit() in R 3.5.0. Upgrading to this version of the R or newer should solve the issue.