The following status values may be returned by the SGS parameter routines.
| SGS__ILLAC | Illegal access mode |
| SGS__TOOZD | No more available zone descriptors |
| SGS__UNKPA | Parameter not found |
The following status values may be returned by the PGPLOT parameter routines.
| PGP__TOOZD | No more available unit descriptors |
| PGP__ILLAC | Illegal access mode |
| PGP__UNKPA | Parameter not found |
| PGP__ISACT | Parameter currently active |
| PGP__ERROR | An error has been reported from GKS itself |
| PGP__DVERR | Workstation name not defined by GNS |
The following status values may be returned by the GKS parameter routines.
| GKS__TOOZD | No more available graphics descriptors |
| GKS__ILLAC | Illegal access mode |
| GKS__UNKPA | Parameter not associated with workstation |
| GKS__ISACT | Parameter currently active |
| GKS__ERROR | An error has been reported from GKS itself |
| GKS__DVERR | Workstation name not defined by GNS |