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+# sum
+
+> Compute checksums and the number of blocks for a file.
+> A predecessor to the more modern `cksum`.
+
+- Compute a checksum with BSD-compatible algorithm and 1024-byte blocks:
+
+`sum {{file}}`
+
+- Compute a checksum with System V-compatible algorithm and 512-byte blocks
+
+`sum --sysv {{file}}`