tar_process.Rd

% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/tar_process.R
\name{tar_process}
\alias{tar_process}
\title{Get main process info.}
\usage{
tar_process(names = NULL, store = targets::tar_config_get("store"))
}
\arguments{
\item{names}{Optional, names of the data points to return.
If supplied, \code{tar_process()}
returns only the rows of the names you select.
The object supplied to \code{names} should be \code{NULL} or a
\code{tidyselect} expression like \code{\link[=any_of]{any_of()}} or \code{\link[=starts_with]{starts_with()}}.}

\item{store}{Character of length 1, path to the
\code{targets} data store. Defaults to \code{tar_config_get("store")},
which in turn defaults to \verb{_targets/}.
When you set this argument, the value of \code{tar_config_get("store")}
is temporarily changed for the current function call.
See \code{\link[=tar_config_get]{tar_config_get()}} and \code{\link[=tar_config_set]{tar_config_set()}} for details
about how to set the data store path persistently
for a project.}
}
\value{
A data frame with metadata on the most recent main R process
to orchestrate the targets of the current project.
The output includes the \code{pid} of the main process.
}
\description{
Get info on the most recent main R process
to orchestrate the targets of the current project.
}
\details{
The main process is the R process invoked
by \code{\link[=tar_make]{tar_make()}} or similar. If \code{callr_function} is not \code{NULL},
this is an external process, and the \code{pid} in the return value
will not agree with \code{Sys.getpid()} in your current interactive session.
The process may or may not be alive. You may want to
check the status with \code{tar_pid() \%in\% ps::ps_pids()}
before running another call to \code{\link[=tar_make]{tar_make()}}
for the same project.
}
\section{Storage access}{

Several functions like \code{tar_make()}, \code{tar_read()}, \code{tar_load()},
\code{tar_meta()}, and \code{tar_progress()} read or modify
the local data store of the pipeline.
The local data store is in flux while a pipeline is running,
and depending on how distributed computing or cloud computing is set up,
not all targets can even reach it. So please do not call these
functions from inside a target as part of a running
pipeline. The only exception is literate programming
target factories in the \code{tarchetypes} package such as \code{tar_render()}
and \code{tar_quarto()}.
}

\examples{
if (identical(Sys.getenv("TAR_EXAMPLES"), "true")) { # for CRAN
tar_dir({ # tar_dir() runs code from a temp dir for CRAN.
tar_script({
  library(targets)
  library(tarchetypes)
  list(
    tar_target(x, seq_len(2)),
    tar_target(y, 2 * x, pattern = map(x))
  )
}, ask = FALSE)
tar_make()
tar_process()
tar_process(pid)
})
}
}
\seealso{
Other data: 
\code{\link{tar_crew}()},
\code{\link{tar_pid}()}
}
\concept{data}