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Changing the CRTPF Command Default Size
Technote

To change the default size for the Create Physical File ( CRTPF ) command, on the operating system command line type the following:

CHGCMDDFT CRTPF ('SIZE(*NOMAX *N *N)')

Press the Enter key. This is described in the help text on the NEWDFT parameter for the CHGCMDDFT command. If the two *Ns are not used, message CPD6273 is given.