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CNTLLEV=

Language element:	data set option
Default:	varies
Engines:	V6, V7, V8, CONCUR
Valid as:	data set option
OpenVMS specifics:	syntax

MEM

demands exclusive access to the file.

REC

allows sharing of the file with record-level locking.

Details

The CNTLLEV= data set option specifies the level at which shared update access to a SAS data set is denied.

With the CONCUR engine, you can request exclusive access to the file, or you can share access with record-level locking.

By default with the concurrency engine, data sets that are opened for input allow shared read access; data sets that are opened for output demand exclusive access; and data sets that are opened for update either allow shared read and shared write access or they retain exclusive access to the file, depending on the method that is used.

For example, you can allow other users both read and write access to a data set that you are opening for input only. By default, only shared read access is allowed. To enable record-level locking for the data set TEST.TWO, use the following statements:

libname test concur '[mydir]';
data test.one;
   set test.two(cntllev=rec);
run;

As another example, suppose you want to both plot and update your file simultaneously by using the FSEDIT procedure. By default, the PLOT procedure opens a data set for exclusive access, even though it only reads the file. To allow concurrent access, use the following statements:

libname test concur '[mydir]';
proc plot data=test.a(cntllev=rec);
run;

Note:   The CNTLLEV= data set option is ignored for output files; output files always retain exclusive access.  

See Also

• CNTLLEV= data set option in SAS Language Reference: Dictionary

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