tpf_enqc_query: Query ECB shared resource

This function determines whether a shared resource that was defined by using the enqc function is being held by the current ECB.

Last updated

Added in 2020.

Format

#include  <tpf/tpfapi.h>
int       tpf_enqc_query(char *enq_name,enum e_qual ss_qual);

enq_name

The pointer to an 8-byte area that contains the shared resource name that you want to query.

ss_qual

Subsystem qualification for the resource. The argument must belong to the enumerated type e_qual, which is defined in the tpfapi.h header file. Use one of the following predefined terms:

QUAL_U: Specifies that subsystem qualification is applied. If this value is specified, the resource name is subsystem unique and is qualified by the database index (DBI) value for the subsystem.
QUAL_S: Specifies that system-wide qualification is applied. If this value is specified, the resource name is not subsystem unique.
Any ECB that issues the enqc function with QUAL_S value specified is enqueued on the same named resource. If two enqc functions are issued with the same resource name but different ss_qual values, two different resource names are assumed to exist.

Normal return

One of the following values are returned:

TPF_ENQC_QUERY_NOT_FOUND: Indicates that the shared resource is not in use.
TPF_ENQC_QUERY_HELD: Indicates that the shared resource is being held by the current ECB.
TPF_ENQC_QUERY_OTHER_ECB: Indicates that the shared resource is being held by an ECB other than the current ECB.

Error return

None.

Programming considerations

None.

Examples

The following example queries a shared resource to see whether it is being held by the current ECB.

if (tpf_enqc_query (“TESTRSC1”,QUAL_S) == TPF_ENQC_QUERY_HELD)
   {
       deqc(“TESTRSC1”,QUAL_S);
        exit(0);
    }