Operating System | QUEL File Extension | Non-QUEL File Extension | Programming Language |
Windows | .osl | none | 4GL/QUEL |
.qcb | .cob | EQUEL/COBOL | |
.qc | .c | EQUEL/C  | |
UNIX | .osl | none | 4GL/QUEL |
.qc | .c | EQUEL/C | |
.qcb | .cob | EQUEL/COBOL | |
.qf | .f | EQUEL/FORTRAN  | |
VMS | .osl | none | 4GL/QUEL |
.qa | .ada | EQUEL/ADA | |
.qc | .c | EQUEL/C | |
.qcb | .cob | EQUEL/COBOL | |
.qf | .for | EQUEL/FORTRAN  |