Instructions that establish the first section
CCW CCW0 CCW1 CNOP COM CSECT
CXD DC DS DSECT EQU LOCTR
LTORG ORG RSECT START USING
COM, CSECT, DSECT, RSECT, and START start a possibly named control section. The other statements start an unnamed control section.
These instructions are always considered a part of the control section in which they appear.
The DSECT, COM, and DXD instructions initiate reference control sections and do not establish the first executable section.
The statements copied into a source module by a COPY instruction determine whether it initiates the first control section.
Any instructions copied by a COPY instruction, or generated by the processing of a macro instruction before the first section, must belong to one of the groups of instructions shown above. Any other instructions cause the assembler to establish the first section.
All the instructions or groups of instructions listed above can also appear as part of a section.
If you specify the PROFILE assembler option the assembler generates a COPY statement as the first statement in the assembly after any ICTL or *PROCESS statements. The copy member should not contain any ICTL or *PROCESS statements.