In case somebody is interested in answer I got it with this C program:
 
#include <stdio.h>
#include <gpm.h>
 
int my_handler(Gpm_Event *event, void *data)
{ if(event->type & GPM_DOWN)
{ if(event->buttons & GPM_B_LEFT)
system("./l.sh");
if(event->buttons & GPM_B_RIGHT)
system("./r.sh");
if(event->buttons & GPM_B_MIDDLE)
system("./m.sh");
}
return 0;
}
 
int main()
{ Gpm_Connect conn;
int c;
conn.eventMask = ~0; /* Want to know about all the events */
conn.defaultMask = 0; /* don't handle anything by default */
conn.minMod = 0; /* want everything */ 
 
if(Gpm_Open(&conn, 0) == -1)
printf("Cannot connect to mouse server\n");
gpm_handler = my_handler;
while((c = Gpm_Getc(stdin)) != EOF)
Gpm_Close();
return 0;
}
/*EOF*/