PCL file extension is for HP-PCL graphics data
HP Printer Control Language
Similar to PCL
$D$ - Data
OS/2 Planner
$DB - Temporary file
dBASE IV
$ED - Editor temporary file
MS C
$LN - TLink response file
Borland C++
$O1 - Pipe file
DOS
$VM - Virtual manager temporary file
Windows 3.x
&&& - Temporary file
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