halpin of type "char".

Hi,

I need a halpin of type "char".  It must hold a char text like : "/opt/linuxcnc"
Then user could set the value by "setp charpin /opt/linuxcnc"

Is there such a option? Or must the hal source code by modified to accieve this?
 

This is an example I've used, to specify an IP address as a string.

RTAPI_MP_STRING(ipaddress,"ESP IP Address");

option extra_setup yes; is required

Example code

Bit more info here:
linuxcnc.org/docs/2.8/html/man/man3/RTAP...Y_STRING.3rtapi.html

Thread where Andy answered my question forum.linuxcnc.org/24-hal-components/426...-when-loading#209746

Hi,

This is nice! It works. Thank you for this.
I attached a template implementation for passing a single string as argument.










 

Hi,

I think i really need a halpin of type "char".
In a upcoming project a .ngc file has to be loaded from the component.
I need to be able to pass a "char array" to a component input pin.

Passing a string at the component init stage is ok, but not usable at runtime.

Do i need to add this "char" pin to the source code?

 

Hal_port might do it for you. New in V 2.9 but badly documented.

Hi Rod,

Thank you for your advice !

I did some research in the mean time, before reading your post.
After editing a few source files it works!

I can now create char's for hal pin and hal parameters and use them with halcommmand.

Hi Rod,

You where right !.

I managed to get the port function working in a example component "port.so"

It sends a string (char array) from point a to point b trough hal.

This example uses one component.
Normally it would serve between at least 2 components.

It is indeed badly documented.
The buffer is allocated by a setsignal command, this is quite unusual.

For the rest it works out of the box ! Many thanks for your advice !