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Updated: July 2017

diffstat (1)


diffstat - output


diffstat [options] [file-specifications]


DIFFSTAT(1)                 General Commands Manual                DIFFSTAT(1)

       diffstat - make histogram from diff-output

       diffstat [options] [file-specifications]

       This  program  reads the output of diff and displays a histogram of the
       insertions, deletions, and modifications per-file.  Diffstat is a  pro-
       gram that is useful for reviewing large, complex patch files.  It reads
       from one or more input files which contain output from diff,  producing
       a histogram of the total lines changed for each file referenced.

       If  the  input  filename ends with .bz2, .gz, .lzma, .z or .Z, diffstat
       will read the uncompressed data via a pipe from the corresponding  pro-
       gram.   It also can infer the compression type from files piped via the
       standard input.

       Diffstat recognizes the most popular types of output from diff:

                     preferred by the patch utility.

                     best for readability, but not very compact.

                     not good for much, but simple to generate.

       Diffstat detects the lines that are output by diff to tell which  files
       are  compared,  and  then  counts  the markers in the first column that
       denote the type of change (insertion, deletion or modification).  These
       are shown in the histogram as "+", "-" and "!" characters.

       If no filename is given on the command line, diffstat reads the differ-
       ences from the standard input.

       -b     ignore lines matching "Binary files XXX and YYY differ"  in  the

       -c     prefix  each  line  of output with "#", making it a comment-line
              for shell scripts.

       -D destination
              specify a directory containing files which can be referred to as
              the result of applying the differences.  diffstat will count the
              lines in the corresponding files (after adjusting the  names  by
              the -p option) to obtain the total number of lines in each file.

              The  remainder, after subtracting modified and deleted lines, is
              shown as "unchanged lines".

       -e file
              redirect standard error to file.

       -f format
              specify the format of the histogram.

              0  for concise, which shows only the value  and  a  single  his-
                 togram code for each of insert (+), delete (-) or modify (!)

              1  for normal output,

              2  to fill in the histogram with dots,

              4  to print each value with the histogram.

              Any  nonzero  value  gives a histogram.  The dots and individual
              values can be combined, e.g., -f6 gives both.

       -h     prints the usage message and exits.

       -k     suppress the merging of filenames in the report.

       -l     lists only the filenames.  No histogram is generated.

       -m     merge insert/delete counts from each "chunk" of the  patch  file
              to approximate a count of the modified lines.

       -n number
              specify  the  minimum  width  used for filenames.  If you do not
              specify this, diffstat uses the length of the longest  filename,
              after stripping common prefixes.

       -N number
              specify the maximum width used for filenames.  Names longer than
              this limit are truncated on the left.  If  you  do  not  specify
              this, diffstat next checks the -n option.

       -o file
              redirect standard output to file.

       -p number
              override  the logic that strips common pathnames, simulating the
              patch "-p" option.

       -q     suppress the "0 files changed" message for empty diffs.

       -r  code
              provides optional rounding  of  the  data  shown  in  histogram,
              rather than truncating with error adjustments.

              0  is  the  default.   No rounding is performed, but accumulated
                 errors are added to following columns.

              1  rounds the data

              2  rounds the data and adjusts the histogram to ensure  that  it
                 displays something if there are any differences even if those
                 would normally be rounded to zero.

       -S source
              this is like the -D option, but specifies a location  where  the
              original files (before applying differences) can be found.

       -t     overrides  the  histogram,  generates  output of comma separated

       -u     suppress the sorting of filenames in the report.

       -v     show progress, e.g., if the output  is  redirected  to  a  file,
              write progress messages to the standard error.

       -V     prints the current version number and exits.

       -w number
              specify  the maximum width of the histogram.  The histogram will
              never be shorter than 10 columns, just in case the filenames get
              too large.

       Diffstat runs in a portable UNIX(R) environment.

       You can override the compiled-in paths of programs used for decompress-
       ing input files by setting environment variables corresponding to their


       However, diffstat assumes that the resulting program uses the same com-
       mand-line options, e.g., "-c" to decompress to the standard output.

       Diffstat is a single binary module, which uses no auxiliary files.

       Diffstat makes a lot of assumptions about the format of a diff file.

       There is no way to obtain a filename from the standard diff between two
       files with no options.  Context diffs work, as well as unified diffs.

       There's  no  easy  way  to  determine the degree of overlap between the
       "before" and "after"  displays  of  modified  lines.   diffstat  simply
       counts the number of inserted and deleted lines to approximate modified
       lines for the -m option.

       See attributes(5) for descriptions of the following attributes:

       |Availability   | text/diffstat    |
       |Stability      | Uncommitted      |
       diff (1).

       Thomas Dickey <dickey@invisible-island.net>.

       This    software    was    built    from    source     available     at
       https://java.net/projects/solaris-userland.    The  original  community
       source was downloaded from   ftp://invisible-island.net/diffstat/diffs-

       Further information about this software can be found on the open source
       community website at http://invisible-island.net/diffstat/.