All letters and numbers are allowed. The assembler discriminates between uppercase and lowercase letters. To the assembler, the variables Name and name identify distinct symbols.
Some blank spaces are required, while others are optional. The assembler allows you to substitute tabs for spaces.
The following characters have special meaning in the AIX assembler language:
The atof subroutine.
The .comm pseudo-op, .csect pseudo-op, .double pseudo-op, .dsect pseudo-op, .float pseudo-op, .lcomm pseudo-op, .tc pseudo-op, .toc pseudo-op, .tocof pseudo-op.