I have a file of large records. Each record spans multiple lines: 
id:999999
Name:John Doe
StreetAddr1:44 Someplace Dr
City:Someplace
State:CA
Zip:99999
MxId:33
Routing:b7
----------
id:789654
Name:Someone Else
StreetAddr1:33 Someotherplace Dr
etc...

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Each record has more fieldname fieldvalue pairs, for the purpose of this example I removed them.

My task is to keep the file format the same but sort the records by Zip. I must admit I'm at a loss as to how to begin. As each record is rather large and the size of the entire file could also be rather large I'm thinking I don't want to slurp the whole file into an array or a hash and then somehow sort that. Any pointers (and I'm not asking you to do the work for me and I'm not asking for code), be they links to modules or a simple explanation of how I would begin would be most helpful.

In reply to Sorting A File Of Large Records by Anonymous Monk

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