. .TH "XXHSUM" "1" "August 2016" "xxhsum 0.6.2" "User Commands" . .SH "NAME" \fBxxhsum\fR \- print or check xxHash non\-cryptographic checksums . .SH "SYNOPSIS" \fBxxhsum\fR [\fIOPTION\fR] \.\.\. [\fIFILE\fR] \.\.\. . .br \fBxxhsum \-b\fR [\fIOPTION\fR] \.\.\. . .P \fBxxh32sum\fR is equivalent to \fBxxhsum \-H0\fR . .br \fBxxh64sum\fR is equivalent to \fBxxhsum \-H1\fR . .SH "DESCRIPTION" Print or check xxHash (32 or 64bit) checksums\. When \fIFILE\fR is \fB\-\fR, read standard input\. . .P \fBxxhsum\fR supports a command line syntax similar but not indentical to md5sum(1)\. Differences are: \fBxxhsum\fR doesn\'t have text/binary mode switch (\fB\-b\fR, \fB\-t\fR); \fBxxhsum\fR always treats file as binary file; \fBxxhsum\fR has hash bit width switch (\fB\-H\fR); . .P As xxHash is a fast non\-cryptographic checksum algorithm, \fBxxhsum\fR should not be used for security related purposes\. . .P \fBxxhsum \-b\fR invokes benchmark mode\. See \fIOPTIONS\fR and \fIEXAMPLES\fR for details\. . .SH "OPTIONS" . .TP \fB\-V\fR, \fB\-\-version\fR Display xxhsum version . .TP \fB\-H\fR\fIHASHTYPE\fR Hash selection\. \fIHASHTYPE\fR means \fB0\fR=32bits, \fB1\fR=64bits\. Default value is \fB1\fR (64bits) . .TP \fB\-\-little\-endian\fR Set output hexadecimal checksum value as little endian convention\. By default, value is displayed as big endian\. . .TP \fB\-h\fR, \fB\-\-help\fR Display help and exit . .P \fBThe following four options are useful only when verifying checksums (\fB\-c\fR)\fR . .TP \fB\-c\fR, \fB\-\-check\fR Read xxHash sums from the \fIFILE\fRs and check them . .TP \fB\-\-quiet\fR Exit non\-zero for improperly formatted checksum lines . .TP \fB\-\-strict\fR Don\'t print OK for each successfully verified file . .TP \fB\-\-status\fR Don\'t output anything, status code shows success . .TP \fB\-w\fR, \fB\-\-warn\fR Warn about improperly formatted checksum lines . .P \fBThe following options are useful only benchmark purpose\fR . .TP \fB\-b\fR Benchmark mode\. See \fIEXAMPLES\fR for details\. . .TP \fB\-B\fR\fIBLOCKSIZE\fR Only useful for benchmark mode (\fB\-b\fR)\. See \fIEXAMPLES\fR for details\. \fIBLOCKSIZE\fR specifies benchmark mode\'s test data block size in bytes\. Default value is 102400 . .TP \fB\-i\fR\fIITERATIONS\fR Only useful for benchmark mode (\fB\-b\fR)\. See \fIEXAMPLES\fR for details\. \fIITERATIONS\fR specifies number of iterations in benchmark\. Single iteration takes at least 2500 milliseconds\. Default value is 3 . .SH "EXIT STATUS" \fBxxhsum\fR exit \fB0\fR on success, \fB1\fR if at least one file couldn\'t be read or doesn\'t have the same checksum as the \fB\-c\fR option\. . .SH "EXAMPLES" Output xxHash (64bit) checksum values of specific files to standard output . .IP "" 4 . .nf $ xxhsum \-H1 foo bar baz . .fi . .IP "" 0 . .P Output xxHash (32bit and 64bit) checksum values of specific files to standard output, and redirect it to \fBxyz\.xxh32\fR and \fBqux\.xxh64\fR . .IP "" 4 . .nf $ xxhsum \-H0 foo bar baz > xyz\.xxh32 $ xxhsum \-H1 foo bar baz > qux\.xxh64 . .fi . .IP "" 0 . .P Read xxHash sums from specific files and check them . .IP "" 4 . .nf $ xxhsum \-c xyz\.xxh32 qux\.xxh64 . .fi . .IP "" 0 . .P Benchmark xxHash algorithm for 16384 bytes data in 10 times\. \fBxxhsum\fR benchmarks xxHash algorithm for 32\-bit and 64\-bit and output results to standard output\. First column means algorithm, second column is source data size in bytes, last column means hash generation speed in mega\-bytes per seconds\. . .IP "" 4 . .nf $ xxhsum \-b \-i10 \-B16384 . .fi . .IP "" 0 . .SH "BUGS" Report bugs at: https://github\.com/Cyan4973/xxHash/issues/ . .SH "AUTHOR" Yann Collet . .SH "SEE ALSO" md5sum(1)