NAME

       gspool_ptrmon - set a function to monitor changes to printers

SYNOPSIS

       #include <gspool.h>

       int gspool_ptrmon(const int fd, void (*fn)(const int))

DESCRIPTION

       Note that this routine is not available in the Windows version, please see the section on
       gspool_setmon, which covers both jobs and printers.  The gspool_ptrmon() function is used
       to set the function fn to be called upon notification of any changes to the printers list.

       fd is a file descriptor previously returned by gspool_open

       fn is a function which must be declared as returning void and taking one "const int"
       argument. Alternatively, this may be "NULL" to cancel monitoring.

       The function fn will be called with fd as an argument upon each change to the printer
       list.

       Please note that any changes to the printer list is reported as the API does not record
       which printers the user is interested in.

RETURN VALUES

       The function gspool_ptrmon() returns 0 if successful otherwise the error code
       "GSPOOL_INVALID_FD" if the file descriptor is invalid. Invalid fn parameters will not be
       detected and the application program will probably crash.

SEE ALSO

       gspool_open(3), gspool_close(3), gspool_joblist(3), gspool_jobmon(3), gspool_ptrlist(3).

COPYRIGHT

       Copyright (c) 2009 Free Software Foundation, Inc.  This is free software. You may
       redistribute copies of it under the terms of the GNU General Public License
       <http://www.gnu.org/licenses/gpl.html>.  There is NO WARRANTY, to the extent permitted by
       law.

AUTHOR

       John M Collins, Xi Software Ltd.