plan9port

[fork] Plan 9 from user space
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sum.1 (1388B)


      1 .TH SUM 1
      2 .SH NAME
      3 sum, md5sum, sha1sum \- sum and count blocks in a file
      4 .SH SYNOPSIS
      5 .B sum
      6 [
      7 .B -5r
      8 ]
      9 [
     10 .I file ...
     11 ]
     12 .PP
     13 .B md5sum
     14 [
     15 .I file ...
     16 ]
     17 .PP
     18 .B sha1sum
     19 [
     20 .I file ...
     21 ]
     22 .SH DESCRIPTION
     23 By default,
     24 .I sum
     25 calculates and prints a 32-bit hexadecimal checksum,
     26 a byte count,
     27 and the name of
     28 each
     29 .IR file .
     30 The checksum is also a function of the input length.
     31 If no files are given,
     32 the standard input is
     33 summed.
     34 Other summing algorithms are available.
     35 The options are
     36 .TP
     37 .B -r
     38 Sum with the algorithm of System V's
     39 .B "sum -r"
     40 and print the length (in 1K blocks) of the input.
     41 .TP
     42 .B -5
     43 Sum with System V's default algorithm
     44 and print the length (in 512-byte blocks) of the input.
     45 .PP
     46 .I Sum
     47 is typically used to look for bad spots,
     48 to validate a file communicated over
     49 some transmission line or
     50 as a quick way to determine if two files on different machines might be the same.
     51 .PP
     52 .B Md5sum
     53 computes the 32 hex digit RSA Data Security, Inc. MD5 Message-Digest Algorithm
     54 described in RFC1321.
     55 If no
     56 .I files
     57 are given,
     58 the standard input is
     59 summed.
     60 .PP
     61 .B Sha1sum
     62 computes the 40 hex digit National Institute of Standards and Technology SHA1 secure hash algorithm
     63 described in FIPS PUB 180-1.
     64 If no
     65 .I files
     66 are given,
     67 the standard input is
     68 summed.
     69 .SH SOURCE
     70 .B \*9/src/cmd/sum.c
     71 .br
     72 .B \*9/src/cmd/md5sum.c
     73 .br
     74 .B \*9/src/cmd/sha1sum.c
     75 .SH "SEE ALSO"
     76 .MR cmp (1) ,
     77 .MR wc (1)