## 3.1.8 Disk Reader Support 

With z/OS 2.4, JES2 provides function similar to the JES3 disk reader DSP. It allows copying of a member from a predefined concatenation of PDSs, PDSEs, and z/OS UNIX directories to an internal reader, passing the records in the member to JES2 input processing. 

This feature is implemented using three constructs that were introduced in z/OS 2.4: 

GLYPH<SM590000> SUBMITLIB: Defines the libraries where the source members is stored. These libraries can be concatenated. 

GLYPH<SM590000> SUBMITRDR statement: Defines the default for the input device. It is similar to the INTRDR statement. 

GLYPH<SM590000> $SUBMIT command: Reads the members and passes them to the input processing. 

## 3.1.9 JES2 Multi Job NJE Job Streams 

Starting with z/OS 2.4, JES2 NJE was updated to support multiple jobs in a single job stream. Before z/OS 2.4, JES2 allowed only job per NJE job stream. If a second job was encountered, all jobs in the stream fail. 

With this support, you can send a set of jobs to a node and have them processed by input processing in the correct order. 

## 3.1.10 JES2 //*ROUTE XEQ Support 

With z/OS 2.3, the support for many JES3 JECL statements was introduced. z/OS 2.4 adds the support for the JES3 //*ROUTE XEQ JECL. The syntax rules are the same as JES3, but the alternative form /*ROUTE XEQ is not supported because of conflicts with the JES2 /*ROUTE XEQ statement. 

## 3.2 JES2-only functions 

Several functions and features are unique to JES2 or behave differently in JES3. In this section, we describe some of these functions. 

## 3.2.1 Job correlator 

The job correlator (JOBCORR) is a 64-byte token that uniquely identifies a job to JES. The JOBCORR value is composed of a 32-byte system portion, which ensures a unique value, and a 32-byte user portion, which helps identify the job to the system. The UJOBCORR parameter of the JOB card specifies this 32-byte user portion of the job correlator. This job correlator provides the following features: 

GLYPH<SM590000> Provides a larger name space for jobs (in addition to classical job name). 

GLYPH<SM590000> Helps relating jobs to output and other records. 

GLYPH<SM590000> Provides a simple way for applications to determine the Job ID of a job that was submitted. 

GLYPH<SM590000> Is available with the z/OSMF REST API. 

The UJOBCORR value can be overridden when the job is submitted by using the appropriate JES2 exits. 

