On Sat, Dec 27, 2003 at 03:31:21PM -0500, Robert P. J. Day wrote: > i just want to clarify the difference between the "Requires" and "PreReq" > directives in a spec file. > > from johnson's book, i read that "In most usage, a PreReq: acts just like > a Requires:...". the stated difference is that PreReq: exists only to allow > for a manual order to dependencies. but what is the technical difference? > > in both cases, if a listed dependency is already on the system, then you're > good to go, so there's no difference there. so the only difference could be > if you're trying to install two packages with some kind of dependency > relationship, in the same command. > > imagine package A, which has a PreReq: or Requires: directive listing > package B, neither of which is on the host at the moment. is it legal in > either case to do > > # rpm -i A.rpm B.rpm > > if A "Requires" B, is the above legal? and does this differ if A lists B as > a PreReq? and, in either case, if the operation is legal, is B forced to be > installed first? or only in the case of B being a PreReq? or is it arbitrary? > The only difference between PreReq: and Requires: has to do with dependency loops (which should not happen anyways). If a loop is encountered, all Requires: in the loop will be ignored, PreReq:'s will be honored. Theere are other means to snip loops more precisely. 73 de Jeff -- Jeff Johnson ARS N3NPQ jbj@xxxxxxxxxx (jbj@xxxxxxx) Chapel Hill, NC _______________________________________________ Rpm-list mailing list Rpm-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/rpm-list
