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Chilkat2-Python

File Read Blocks

Demonstrates how to read a file in fixed-size blocks (except for the very last block).

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Chilkat2-Python
import sys
import chilkat2

success = False

# Demonstrates how to read a file in blocks,
# which can be useful when uploading to cloud storage
# services such as Azure, S3, Google, etc.

# For this example, we're simply writing the blocks
# to an output file, and then checking to see if the
# resulting file contents equals the original file contents.

facSrc = chilkat2.FileAccess()
facDest = chilkat2.FileAccess()

srcPath = "qa_data/xml/hamlet.xml"
destPath = "qa_output/hamletOut.xml"

success = facSrc.OpenForRead(srcPath)
success = facDest.OpenForWrite(destPath)
# Assuming success for the example..

# How many 1024-byte blocks?  (Including 1 for the last partial block)
numBlocks = facSrc.GetNumBlocks(1024)

i = 0
while (i < numBlocks) :
    # dataBlock is a memoryview
    dataBlock = facSrc.ReadBlock(i,1024)
    if (facSrc.LastMethodSuccess != True):
        print(facSrc.LastErrorText)
        sys.exit()

    success = facDest.FileWrite(dataBlock)
    if (success != True):
        print(facDest.LastErrorText)
        sys.exit()

    i = i + 1

facSrc.FileClose()
facDest.FileClose()

bEqual = facSrc.FileContentsEqual(srcPath,destPath)
if (bEqual != True):
    print("Something went wrong!")
    sys.exit()

print("File successfully copied by blocks.")