| CHARACTER_STORAGE_SIZE Size of a character in bits. | |
| ERROR_UNIT Unit number for standard error. | |
| FILE_STORAGE_SIZE Size of the file storage unit in bits. | |
| INPUT_UNIT Unit number for standard input. | |
| IOSTAT_END Value assigned to IOSTAT variables at end-of-file. | |
| IOSTAT_EOR Value assigned to IOSTAT variables at end-of-record. | |
| NUMERIC_STORAGE_SIZE Size of the numeric storage unit in bits. | |
| OUTPUT_UNIT Unit number for standard output. |