Change Physical File (CHGPF) command

The Change Physical File (CHGPF) command's life purpose is to change the attributes of a physical file and all its members. The Change Physical File command (CHGPF) can be run either through a 5250 terminal session (green-screen) or through iSeries Navigator's (OpsNav) Run Command facility, which allow you to run green-screen commands through a Windows interface. (For more information on using Run Command, see the articles in the Related Stories section at the bottom of this article.)

CHGPF can be used to change several significant file attributes, including the maximum number of members the file can contain, the member size, some performance parameters, and the source file member that the file's field and key descriptions are based on.
http://www.code400.com/forum/showthread.php/8661-Chgpf
http://search400.techtarget.com/tip/Using-CHGPF-to-handle-file-changes-with-ease
http://publib.boulder.ibm.com/infocenter/iseries/v5r4/index.jsp?topic=%2Fcl%2Fchgpf.htm
http://publib.boulder.ibm.com/iseries/v5r1/ic2924/index.htm?info/cl/chgpf.htm