problem with COPY command

I have a problem to populate a database with the copy command

my write command are:

> COPY telefono FROM '/home/alain/Documents/prueba2.txt'
> WITH DELIMITER AS ',';

The pgsql server answer the following:

> ERROR: COPY command, running in backend with effective uid 26, could
> not open file '/home/alain/Documents/prueba2.txt' for reading. Errno
> = Permiso denegado (13).

Thank you for your atention

Alain Hermosilla
ahermosi(at)lonquensur(dot)cl