| % File src/library/utils/man/unix/nsl.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2018 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{nsl} |
| \alias{nsl} |
| \title{Look up the IP Address by Hostname (on Unix-alikes)} |
| \description{ |
| Interface to the system \command{gethostbyname}, currently available |
| only on unix-alikes, i.e., not on Windows. |
| } |
| \usage{ |
| nsl(hostname) |
| } |
| \arguments{ |
| \item{hostname}{the name of the host.} |
| } |
| \value{ |
| The IP address, as a character string, or \code{NULL} if the call fails. |
| } |
| \details{ |
| This was included as a test of internet connectivity, to fail if |
| the node running \R is not connected. It will also return \code{NULL} |
| if BSD networking is not supported, including the header file |
| \file{arpa/inet.h}. |
| |
| This function is not available on Windows. |
| } |
| \examples{ |
| if(.Platform$OS.type == "unix") # includes Mac |
| print( nsl("www.r-project.org") ) |
| } |
| \keyword{utilities} |