R/run_system_cmd.R

In SticsRPacks/SticsOnR: Manage STICS Simulations Running the Executable or JavaStics,

#' Run a system command
#'
#' @param command A system command
#' @param com_args A list of arguments to pass to the command
#' @param output A logical value to specify returning (T) or not (F, default)
#' the command output in the function return "output" attribute
#'
#' @return A logical status TRUE if it succeded or FALSE if not
#' a "message" attribute is set with an error message, and optionaly
#' an "output" attribute is set with the command output
#'
#' @keywords internal
#'
#' @noRd
#'
run_system_cmd <- function(command, com_args = "", output = FALSE) {

  # To fix command as an absolute path to the executable
  command <- normalizePath(command)

  err_status <- TRUE
  ret <- try(system2(
    command = command, args = com_args,
    stderr = TRUE,
    stdout = TRUE
  ),
  silent = TRUE
  )
  # 'print(ret)

  # if any error, storing message as an attribute
  if ("class" %in% names(attributes(ret)) &&
    attr(ret, "class") == "try-error") {
    err_status <- FALSE
    attr(err_status, "message") <- ret[1]
    return(err_status)
  }

  # Not a try-error ??? Why ?
  # TODO: to be merged with preceeding conditionnal block !!!!!
  if ("status" %in% names(attributes(ret)) &&
    attr(ret, "status") > 0) {
    err_status <- FALSE
    attr(err_status, "message") <- ret[1]
    return(err_status)
  }


  # Attaching the command output as a status attribute
  if (length(ret)) {
    if (output) attr(err_status, "output") <- ret
  }

  return(invisible(err_status))
}