Xbase++

Set a Custom Last-Modified Date in a Gzip File

See more Gzip Examples

This example demonstrates how to use the SetDt method to specify a custom last-modified date and time that will be embedded in a Gzip file.

A CkDateTime object is first initialized with a specific date/time using an RFC 822 formatted string. This date/time is then applied to the Gzip object using SetDt.

When a compression method is called (such as CompressStringToFile), the specified date/time is included in the Gzip metadata. This allows the resulting .gz file to carry a meaningful timestamp rather than using the current system time.

Xbase++

LOCAL nSuccess
LOCAL oGzip
LOCAL oDt
LOCAL cInputStr

nSuccess := 0

//  This example demonstrates how to set a custom last-modified date/time
//  that will be embedded in a Gzip file.

oGzip := CreateObject("Chilkat.Gzip")
oDt := CreateObject("Chilkat.CkDateTime")

//  Set the date/time using a timestamp format (ISO 8601 style):
oDt:SetFromTimestamp("2025-11-15T12:45:26-05:00")

//  Apply the date/time to the Gzip object:
nSuccess := oGzip:SetDt(oDt)
IF (nSuccess == 0)
    ? oGzip:LastErrorText
    oGzip:destroy()
    oDt:destroy()
    RETURN
ENDIF

//  Compress a string so the custom date/time is embedded in the .gz:
cInputStr := "Example text for Gzip compression."
nSuccess := oGzip:CompressStringToFile(cInputStr, "utf-8", "output.gz")
IF (nSuccess == 0)
    ? oGzip:LastErrorText
    oGzip:destroy()
    oDt:destroy()
    RETURN
ENDIF

? "Gzip file created with custom last-modified date."

oGzip:destroy()
oDt:destroy()