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GN_Opf, file or stream open
GN_Cl, close file
GN_Del, delete a file from memory
GN_Ren, rename file
OS_Cl, internal close (OZ usage)
OS_Del, file delete (OZ usage)
OS_Frm, file read miscellaneous
OS_Fwm, file write miscellaneous
OS_Gb, get byte from file (or device)
OS_Gbt, get byte from file (or device) with timeout
OS_Mv, move bytes between stream and memory
OS_Op, internal open (OZ usage)
OS_Pb, write byte to file, device
OS_Pbt, write byte to file, device with timeout
OS_Ren, file rename (OZ usage)
Serial port stream operations
OS_Pb, write byte to serial port device (IX handle)
OS_Pbt, write byte to serial port device (IX handle), with timeout
OS_Gb, get byte from serial port device (IX handle)
OS_Gbt, get byte from serial port device (IX handle) with timeout
OS_Si, low level serial port interface
Filenames
GN_Esa, read & write to filename segments
GN_Fcm, produce compressed filename
GN_Fex, expand a filename
GN_Opw, open wildcard handler
GN_Pfs, parse filename segment
GN_Prs, parse filename
GN_Wcl, close wildcard handle
GN_Wfn, fetch next match for wildcard string (handle)
GN_Wsm, match filename segment to wildcard string
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