telnetd Telnet server daemon

This is the Telnet logic adapted from uIP and generalized for use as the front end to any shell. The telnet daemon creates sessions that are “wrapped” as character devices and mapped to stdin, stdout and stderr. Now the telnet session can be inherited by spawned tasks.

Tips for Using Telnetd

Telnetd is set up to be the front end for a shell. The primary use of Telnetd in NuttX is to support the NuttShell (NSH) Telnet front end. See apps/include/netutils/telnetd.h for information about how to incorporate Telnetd into your custom applications.

To enable and link the Telnetd daemon, you need to include the following in in your defconfig file:

CONFIG_NETUTILS_NETLIB=y
CONFIG_NETUTILS_TELNETD=y

Also if the Telnet console is enabled, make sure that you have the following set in the NuttX configuration file or else the performance will be very bad (because there will be only one character per TCP transfer):

• CONFIG_STDIO_BUFFER_SIZE – Some value >= 64.

• CONFIG_STDIO_LINEBUFFER=y – Since Telnetd is line oriented, line buffering is optimal.