Now that we have basic functionality lets make some custom commands.

The prototype for commands can be seen here 

I am going to make a simple command called "ok" and it will display a message saying that everything is ok. 

Below is my commands.c file in its entirety as of right now:

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#include "FreeRTOS.h"
#include "FreeRTOS_CLI.h"
#include "main.h"
#include "main_app.h"

static BaseType_t cmd_ok(int8_t *pcWriteBuffer, size_t xWriteBufferLen, const int8_t *pcCommandString);

static BaseType_t cmd_ok(int8_t *pcWriteBuffer, size_t xWriteBufferLen, const int8_t *pcCommandString)
{
    const char *const okMessage = "everything OK! \r\n";

    memset(pcWriteBuffer, 0x00, xWriteBufferLen);
    /* Generate a table of task stats. */
    strcpy(pcWriteBuffer, okMessage);
    /* There is no more data to return after this single string, so return
        pdFALSE. */
    return pdFALSE;
}

static const CLI_Command_Definition_t xCmdOK = {
    "ok",                               // command to type
    "ok :\r\n Shows an OK message\r\n", // help string
    cmd_ok,                             // command handler
    0                                   // num of pasrameters to expect
};

void vRegisterCLICommands(void)
{
    FreeRTOS_CLIRegisterCommand(&xCmdOK);
}

• Line 6 : is the function prototype for my command. That has to be the function signature of all FreeRTOS CLI commands.
• Lines 8 - 18 : Is the implementation of the function itself. 
• Line 10 : This is simply a string with the message I want to display
• Line 12 : Clears the buffer that FreeRTOS  CLI uses to print messages from within commands
• Line 14 : Copies the string into the buffer
• Line 17 : Returns false, I will sure you later on what condition you want to return true
• Line 20 - 25 : Makes a struct that is used to register a command.
• Line 20 : This is a FreeRTOS predefined struct type and xCmdOk is simply the name I assigned this command when registering it.
• Line 21 : Is the string you will type in the CLI to call the command
• Line 22 : Is the help message that will correspond to this command 
• Line 23 : Is the function that will be called to handle the command
• Line 24 : Is the number of parameters this command expects
• Line 27 : Is a function I made that registers all commands .

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void vCommandConsoleTask(void *pvParameters)
{
    int8_t cInputIndex = 0;
    BaseType_t xMoreDataToFollow;
    /* The input and output buffers are declared static to keep them off the
     * stack. */
    static int8_t pcOutputString[MAX_OUTPUT_LENGTH], pcInputString[MAX_INPUT_LENGTH];

    vRegisterCLICommands();

    for (;;)
    {

So how can we improve this basic CLI?

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