NAME | SYNOPSIS | DESCRIPTION | OPTIONS | INVOKING INDENT | BACKUP FILES | COMMON STYLES | BLANK LINES | --blank-lines-after-declarations | --blank-lines-after-procedures | COMMENTS | STATEMENTS | DECLARATIONS | INDENTATION | BREAKING LONG LINES | DISABLING FORMATTING | MISCELLANEOUS OPTIONS | BUGS | COPYRIGHT | Options’ Cross Key | RETURN VALUE | FILES | AUTHORS | HISTORY | COPYING | COLOPHON

INDENT(1L)                                                        INDENT(1L)

NAME         top

       indent - changes the appearance of a C program by inserting or delet‐
       ing whitespace.

SYNOPSIS         top

       indent [options] [input-files]

       indent [options] [single-input-file] [-o output-file]

       indent --version

DESCRIPTION         top

       This man page is generated from the file indent.texinfo.  This is
       Edition  of "The indent Manual", for Indent Version , last updated .

       The indent program can be used to make code easier to read.  It can
       also convert from one style of writing C to another.

       indent understands a substantial amount about the syntax of C, but it
       also attempts to cope with incomplete and misformed syntax.

       In version 1.2 and more recent versions, the GNU style of indenting
       is the default.

OPTIONS         top

       -bad, --blank-lines-after-declarations
           Force blank lines after the declarations.
           See  BLANK LINES.

       -bap, --blank-lines-after-procedures
           Force blank lines after procedure bodies.
           See  BLANK LINES.

       -bbb, --blank-lines-before-block-comments
           Force blank lines before block comments.
           See  BLANK LINES.

       -bbo, --break-before-boolean-operator
           Prefer to break long lines before boolean operators.
           See  BREAKING LONG LINES.

       -bc, --blank-lines-after-commas
           Force newline after comma in declaration.
           See  DECLARATIONS.

       -bl, --braces-after-if-line
           Put braces on line after if, etc.
           See  STATEMENTS.

       -blf, --braces-after-func-def-line
           Put braces on line following function definition line.
           See  DECLARATIONS.

       -blin, --brace-indentn
           Indent braces n spaces.
           See  STATEMENTS.

       -bls, --braces-after-struct-decl-line
           Put braces on the line after struct declaration lines.
           See  DECLARATIONS.

       -br, --braces-on-if-line
           Put braces on line with if, etc.
           See  STATEMENTS.

       -brf, --braces-on-func-def-line
           Put braces on function definition line.
           See  DECLARATIONS.

       -brs, --braces-on-struct-decl-line
           Put braces on struct declaration line.
           See  DECLARATIONS.

       -bs, --Bill-Shannon, --blank-before-sizeof
           Put a space between sizeof and its argument.
           See  STATEMENTS.

       -cn, --comment-indentationn
           Put comments to the right of code in column n.
           See  COMMENTS.

       -cbin, --case-brace-indentationn
           Indent braces after a case label N spaces.
           See  STATEMENTS.

       -cdn, --declaration-comment-columnn
           Put comments to the right of the declarations in column n.
           See  COMMENTS.

       -cdb, --comment-delimiters-on-blank-lines
           Put comment delimiters on blank lines.
           See  COMMENTS.

       -cdw, --cuddle-do-while
           Cuddle while of do {} while; and preceding ‘}’.
           See  COMMENTS.

       -ce, --cuddle-else
           Cuddle else and preceding ‘}’.
           See  COMMENTS.

       -cin, --continuation-indentationn
           Continuation indent of n spaces.
           See  STATEMENTS.

       -clin, --case-indentationn
           Case label indent of n spaces.
           See  STATEMENTS.

       -cpn, --else-endif-columnn
           Put comments to the right of #else and #endif statements in
           column n.
           See  COMMENTS.

       -cs, --space-after-cast
           Put a space after a cast operator.
           See  STATEMENTS.

       -dn, --line-comments-indentationn
           Set indentation of comments not to the right of code to n spaces.
           See  COMMENTS.

       -bfda, --break-function-decl-args
           Break the line before all arguments in a declaration.
           See  DECLARATIONS.

       -bfde, --break-function-decl-args-end
           Break the line after the last argument in a declaration.
           See  DECLARATIONS.

       -dj, --left-justify-declarations
           If -cd 0 is used then comments after declarations are left
           justified behind the declaration.
           See  DECLARATIONS.

       -din, --declaration-indentationn
           Put variables in column n.
           See  DECLARATIONS.

       -fc1, --format-first-column-comments
           Format comments in the first column.
           See  COMMENTS.

       -fca, --format-all-comments
           Do not disable all formatting of comments.
           See  COMMENTS.

       -fnc, --fix-nested-comments
           Fix nested comments.
           See  COMMENTS.

       -gnu, --gnu-style
           Use GNU coding style.  This is the default.
           See  COMMON STYLES.

       -gts, --gettext-strings
           Treat gettext _("...") and N_("...") as strings rather than as
           functions.
           See  BREAKING LONG LINES.

       -hnl, --honour-newlines
           Prefer to break long lines at the position of newlines in the
           input.
           See  BREAKING LONG LINES.

       -in, --indent-leveln
           Set indentation level to n spaces.
           See  INDENTATION.

       -iln, --indent-labeln
           Set offset for labels to column n.
           See  INDENTATION.

       -ipn, --parameter-indentationn
           Indent parameter types in old-style function definitions by n
           spaces.
           See  INDENTATION.

       -kr, --k-and-r-style
           Use Kernighan & Ritchie coding style.
           See  COMMON STYLES.

       -ln, --line-lengthn
           Set maximum line length for non-comment lines to n.
           See  BREAKING LONG LINES.

       -lcn, --comment-line-lengthn
           Set maximum line length for comment formatting to n.
           See  COMMENTS.

       -linux, --linux-style
           Use Linux coding style.
           See  COMMON STYLES.

       -lp, --continue-at-parentheses
           Line up continued lines at parentheses.
           See  INDENTATION.

       -lps, --leave-preprocessor-space
           Leave space between ‘#’ and preprocessor directive.
           See  INDENTATION.

       -nbad, --no-blank-lines-after-declarations
           Do not force blank lines after declarations.
           See  BLANK LINES.

       -nbap, --no-blank-lines-after-procedures
           Do not force blank lines after procedure bodies.
           See  BLANK LINES.

       -nbbo, --break-after-boolean-operator
           Do not prefer to break long lines before boolean operators.
           See  BREAKING LONG LINES.

       -nbc, --no-blank-lines-after-commas
           Do not force newlines after commas in declarations.
           See  DECLARATIONS.

       -nbfda, --dont-break-function-decl-args
           Don’t put each argument in a function declaration on a separate
           line.
           See  DECLARATIONS.

       -ncdb, --no-comment-delimiters-on-blank-lines
           Do not put comment delimiters on blank lines.
           See  COMMENTS.

       -ncdw, --dont-cuddle-do-while
           Do not cuddle } and the while of a do {} while;.
           See  STATEMENTS.

       -nce, --dont-cuddle-else
           Do not cuddle } and else.
           See  STATEMENTS.

       -ncs, --no-space-after-casts
           Do not put a space after cast operators.
           See  STATEMENTS.

       -ndjn, --dont-left-justify-declarations
           Comments after declarations are treated the same as comments
           after other statements.
           See  DECLARATIONS.

       -nfc1, --dont-format-first-column-comments
           Do not format comments in the first column as normal.
           See  COMMENTS.

       -nfca, --dont-format-comments
           Do not format any comments.
           See  COMMENTS.

       -ngts, --no-gettext-strings
           Treat gettext _("...") and N_("...") as normal functions.  This
           is the default.
           See  BREAKING LONG LINES.

       -nhnl, --ignore-newlines
           Do not prefer to break long lines at the position of newlines in
           the input.
           See  BREAKING LONG LINES.

       -nip, --no-parameter-indentation
           Zero width indentation for parameters.
           See  INDENTATION.

       -nlp, --dont-line-up-parentheses
           Do not line up parentheses.
           See  STATEMENTS.

       -npcs, --no-space-after-function-call-names
           Do not put space after the function in function calls.
           See  STATEMENTS.

       -nprs, --no-space-after-parentheses
           Do not put a space after every ’(’ and before every ’)’.
           See  STATEMENTS.

       -npsl, --dont-break-procedure-type
           Put the type of a procedure on the same line as its name.
           See  DECLARATIONS.

       -nsaf, --no-space-after-for
           Do not put a space after every for.
           See  STATEMENTS.

       -nsai, --no-space-after-if
           Do not put a space after every if.
           See  STATEMENTS.

       -nsaw, --no-space-after-while
           Do not put a space after every while.
           See  STATEMENTS.

       -nsc, --dont-star-comments
           Do not put the ‘*’ character at the left of comments.
           See  COMMENTS.

       -nsob, --leave-optional-blank-lines
           Do not swallow optional blank lines.
           See  BLANK LINES.

       -nss, --dont-space-special-semicolon
           Do not force a space before the semicolon after certain
           statements.  Disables ‘-ss’.
           See  STATEMENTS.

       -nut, --no-tabs
           Use spaces instead of tabs.
           See  INDENTATION.

       -nv, --no-verbosity
           Disable verbose mode.
           See  MISCELLANEOUS OPTIONS.

       -orig, --original
           Use the original Berkeley coding style.
           See  COMMON STYLES.

       -npro, --ignore-profile
           Do not read ‘.indent.pro’ files.
           See  INVOKING INDENT.

       -pal, --pointer-align-left
           Put asterisks in pointer declarations on the left of spaces, next
           to types: ‘‘char* p’’.

       -par, --pointer-align-right
           Put asterisks in pointer declarations on the right of spaces,
           next to variable names: ‘‘char *p’’. This is the default
           behavior.

       -pcs, --space-after-procedure-calls
           Insert a space between the name of the procedure being called and
           the ‘(’.
           See  STATEMENTS.

       -pin, --paren-indentationn
           Specify the extra indentation per open parentheses ’(’ when a
           statement is broken.See  STATEMENTS.

       -pmt, --preserve-mtime
           Preserve access and modification times on output files.See
            MISCELLANEOUS OPTIONS.

       -ppin, --preprocessor-indentationn
           Specify the indentation for preprocessor conditional
           statements.See  INDENTATION.

       -prs, --space-after-parentheses
           Put a space after every ’(’ and before every ’)’.
           See  STATEMENTS.

       -psl, --procnames-start-lines
           Put the type of a procedure on the line before its name.
           See  DECLARATIONS.

       -saf, --space-after-for
           Put a space after each for.
           See  STATEMENTS.

       -sai, --space-after-if
           Put a space after each if.
           See  STATEMENTS.

       -saw, --space-after-while
           Put a space after each while.
           See  STATEMENTS.

       -sbin, --struct-brace-indentationn
           Indent braces of a struct, union or enum N spaces.
           See  STATEMENTS.

       -sc, --start-left-side-of-comments
           Put the ‘*’ character at the left of comments.
           See  COMMENTS.

       -sob, --swallow-optional-blank-lines
           Swallow optional blank lines.
           See  BLANK LINES.

       -ss, --space-special-semicolon
           On one-line for and while statements, force a blank before the
           semicolon.
           See  STATEMENTS.

       -st, --standard-output
           Write to standard output.
           See  INVOKING INDENT.

       -T  Tell indent the name of typenames.
           See  DECLARATIONS.

       -tsn, --tab-sizen
           Set tab size to n spaces.
           See  INDENTATION.

       -ut, --use-tabs
           Use tabs. This is the default.
           See  INDENTATION.

       -v, --verbose
           Enable verbose mode.
           See  MISCELLANEOUS OPTIONS.

       -version
           Output the version number of indent.
           See  MISCELLANEOUS OPTIONS.

INVOKING INDENT         top

       As of version 1.3, the format of the indent command is:

            indent [options] [input-files]

            indent [options] [single-input-file] [-o output-file]

       This format is different from earlier versions and other versions  of
       indent.

       In  the  first  form,  one or more input files are specified.  indent
       makes a backup copy of each file, and the original file  is  replaced
       with  its  indented version.  See BACKUP FILES, for an explanation of
       how backups are made.

       In the second form, only one input file is specified.  In this  case,
       or  when  the  standard input is used, you may specify an output file
       after the ‘-o’ option.

       To cause indent to write to standard output, use  the  ‘-st’  option.
       This  is  only allowed when there is only one input file, or when the
       standard input is used.

       If no input files are named, the standard input is  read  for  input.
       Also,  if  a filename named ‘-’ is specified, then the standard input
       is read.

       As an example, each of the following commands will input the  program
       ‘slithy_toves.c’ and write its indented text to ‘slithy_toves.out’:

            indent slithy_toves.c -o slithy_toves.out

            indent -st slithy_toves.c > slithy_toves.out

            cat slithy_toves.c | indent -o slithy_toves.out

       Most  other options to indent control how programs are formatted.  As
       of version 1.2, indent also recognizes a long name  for  each  option
       name.   Long  options  are  prefixed by either ‘--’ or ‘+’.  [ ‘+’ is
       being superseded by ‘--’  to  maintain  consistency  with  the  POSIX
       standard.]
        In  most of this document, the traditional, short names are used for
       the sake of brevity.  See OPTION SUMMARY,  for  a  list  of  options,
       including both long and short names.

       Here is another example:

            indent -br test/metabolism.c -l85

       This  will indent the program ‘test/metabolism.c’ using the ‘-br’ and
       ‘-l85’ options, write the output  back  to  ‘test/metabolism.c’,  and
       write  the  original contents of ‘test/metabolism.c’ to a backup file
       in the directory ‘test’.

       Equivalent invocations using long option names for this example would
       be:

            indent --braces-on-if-line --line-length185 test/metabolism.c

            indent +braces-on-if-line +line-length185 test/metabolism.c

       If  you find that you often use indent with the same options, you may
       put those options into a file named ‘.indent.pro’.  indent will  look
       for  a  profile  file  in  three  places.  First  it  will  check the
       environment variable INDENT_PROFILE. If  that  exists  its  value  is
       expected  to  name  the  file  that is to be used. If the environment
       variable does not  exist,  indent  looks  for  ‘.indent.pro’  in  the
       current directory
        and  use  that  if  found.   Finally  indent  will  search your home
       directory for ‘.indent.pro’ and use that file if it is  found.   This
       behaviour  is  different from that of other versions of indent, which
       load both files if they both exist.

       The format of ‘.indent.pro’ is simply a list of options, just as they
       would  appear  on  the  command line, separated by white space (tabs,
       spaces, and newlines).  Options in ‘.indent.pro’ may be surrounded by
       C or C++ comments, in which case they are ignored.

       Command  line  switches  are  handled after processing ‘.indent.pro’.
       Options specified later override arguments  specified  earlier,  with
       one   exception:   Explicitly   specified   options  always  override
       background options (See COMMON STYLES).  You can prevent indent  from
       reading an ‘.indent.pro’ file by specifying the ‘-npro’ option.

BACKUP FILES         top

       As of version 1.3, GNU indent makes GNU-style backup files, the same
       way GNU Emacs does.  This means that either simple or numbered backup
       filenames may be made.

       Simple backup file names are generated by appending a suffix to the
       original file name.  The default for this suffix is the one-character
       string ‘~’ (tilde).  Thus, the backup file for ‘python.c’ would be
       ‘python.c~’.

       Instead of the default, you may specify any string as a suffix by
       setting the environment variable SIMPLE_BACKUP_SUFFIX to your
       preferred suffix.

       Numbered backup versions of a file ‘momeraths.c’ look like
       ‘momeraths.c.~23~’, where 23 is the version of this particular
       backup.  When making a numbered backup of the file ‘src/momeraths.c’,
       the backup file will be named ‘src/momeraths.c.~V~’, where V is one
       greater than the highest version currently existing in the directory
       ‘src’.  The environment variable VERSION_WIDTH controls the number of
       digits, using left zero padding when necessary.  For instance,
       setting this variable to "2" will lead to the backup file being named
       ‘momeraths.c.~04~’.

       The type of backup file made is controlled by the value of the
       environment variable VERSION_CONTROL.  If it is the string ‘simple’,
       then only simple backups will be made.  If its value is the string
       ‘numbered’, then numbered backups will be made.  If its value is
       ‘numbered-existing’, then numbered backups will be made if there
       already exist numbered backups for the file being indented;
       otherwise, a simple backup is made.  If VERSION_CONTROL is not set,
       then indent assumes the behaviour of ‘numbered-existing’.

       Other versions of indent use the suffix ‘.BAK’ in naming backup
       files.  This behaviour can be emulated by setting
       SIMPLE_BACKUP_SUFFIX to ‘.BAK’.

       Note also that other versions of indent make backups in the current
       directory, rather than in the directory of the source file as GNU
       indent now does.

COMMON STYLES         top

       There are several common styles of C code, including the GNU style,
       the Kernighan & Ritchie style, and the original Berkeley style.  A
       style may be selected with a single background option, which
       specifies a set of values for all other options.  However, explicitly
       specified options always override options implied by a background
       option.

       As of version 1.2, the default style of GNU indent is the GNU style.
       Thus, it is no longer necessary to specify the option ‘-gnu’ to
       obtain this format, although doing so will not cause an error.
       Option settings which correspond to the GNU style are:

            -nbad -bap -nbc -bbo -bl -bli2 -bls -ncdb -nce -cp1 -cs -di2
            -ndj -nfc1 -nfca -hnl -i2 -ip5 -lp -pcs -nprs -psl -saf -sai
            -saw -nsc -nsob

       The GNU coding style is that preferred by the GNU project.  It is the
       style that the GNU Emacs C mode encourages and which is used in the C
       portions  of  GNU  Emacs.  (People interested in writing programs for
       Project GNU should get a copy of "The GNU  Coding  Standards",  which
       also covers semantic and portability issues such as memory usage, the
       size of integers, etc.)

       The Kernighan & Ritchie style is  used  throughout  their  well-known
       book  "The  C  Programming  Language".   It is enabled with the ‘-kr’
       option.  The Kernighan & Ritchie style corresponds to  the  following
       set of options:

            -nbad -bap -bbo -nbc -br -brs -c33 -cd33 -ncdb -ce -ci4 -cli0
            -cp33 -cs -d0 -di1 -nfc1 -nfca -hnl -i4 -ip0 -l75 -lp -npcs
            -nprs -npsl -saf -sai -saw -nsc -nsob -nss

       Kernighan  & Ritchie style does not put comments to the right of code
       in the same column at all times (nor does it use only  one  space  to
       the  right  of  the  code),  so for this style indent has arbitrarily
       chosen column 33.

       The style  of  the  original  Berkeley  indent  may  be  obtained  by
       specifying  ‘-orig’  (or  by  specifying ‘--original’, using the long
       option name).  This style is equivalent to the following settings:

            -nbad -nbap -bbo -bc -br -brs -c33 -cd33 -cdb -ce -ci4 -cli0
            -cp33 -di16 -fc1 -fca -hnl -i4 -ip4 -l75 -lp -npcs -nprs -psl
            -saf -sai -saw -sc -nsob -nss -ts8

       The Linux style is used in the linux kernel code  and  drivers.  Code
       generally  has to follow the Linux coding style to be accepted.  This
       style is equivalent to the following settings:

            -nbad -bap -nbc -bbo -hnl -br -brs -c33 -cd33 -ncdb -ce -ci4
            -cli0 -d0 -di1 -nfc1 -i8 -ip0 -l80 -lp -npcs -nprs -npsl -sai
            -saf -saw -ncs -nsc -sob -nfca -cp33 -ss -ts8 -il1

BLANK LINES         top

       Various programming styles use blank lines in different places.
       indent has a number of options to insert or delete blank lines in
       specific places.

       The ‘-bad’ option causes indent to force a blank line after every
       block of declarations.  The ‘-nbad’ option causes indent not to force
       such blank lines.

       The ‘-bap’ option forces a blank line after every procedure body.
       The ‘-nbap’ option forces no such blank line.

       The ‘-bbb’ option forces a blank line before every boxed comment (See
       COMMENTS.)  The ‘-nbbb’ option does not force such blank lines.

       The ‘-sob’ option causes indent to swallow optional blank lines (that
       is, any optional blank lines present in the input will be removed
       from the output).  If the ‘-nsob’ is specified, any blank lines
       present in the input file will be copied to the output file.

--blank-lines-after-declarations         top

       The ‘-bad’ option forces a blank line after every block of
       declarations.  The ‘-nbad’ option does not add any such blank lines.

       For example, given the input
            char *foo;
            char *bar;
            /* This separates blocks of declarations.  */
            int baz;

       indent -bad produces

            char *foo;
            char *bar;

            /* This separates blocks of declarations.  */
            int baz;

       and indent -nbad produces

            char *foo;
            char *bar;
            /* This separates blocks of declarations.  */
            int baz;

--blank-lines-after-procedures         top

       The ‘-bap’ option forces a blank line after every procedure body.

       For example, given the input

            int
            foo ()
            {
              puts("Hi");
            }
            /* The procedure bar is even less interesting.  */
            char *
            bar ()
            {
              puts("Hello");
            }

       indent -bap produces

            int
            foo ()
            {
              puts ("Hi");
            }

            /* The procedure bar is even less interesting.  */
            char *
            bar ()
            {
              puts ("Hello");
            }

       and indent -nbap produces

            int
            foo ()
            {
              puts ("Hi");
            }
            /* The procedure bar is even less interesting.  */
            char *
            bar ()
            {
              puts ("Hello");
            }

       No blank line will be added after the procedure foo.

COMMENTS         top

       indent formats both C and C++ comments. C comments are begun with
       ‘/*’, terminated with ‘*/’ and may contain newline characters.  C++
       comments begin with the delimiter ‘//’ and end at the newline.

       indent handles comments differently depending upon their context.
       indent attempts to distinguish between comments which follow
       statements, comments which follow declarations, comments following
       preprocessor directives, and comments which are not preceded by code
       of any sort, i.e., they begin the text of the line (although not
       necessarily in column 1).

       indent further distinguishes between comments found outside of
       procedures and aggregates, and those found within them.  In
       particular, comments beginning a line found within a procedure will
       be indented to the column at which code is currently indented.  The
       exception to this is a comment beginning in the leftmost column;
       such a comment is output at that column.

       indent attempts to leave boxed comments unmodified. The general idea
       of such a comment is that it is enclosed in a rectangle or ‘‘box’’ of
       stars or dashes to visually set it apart.  More precisely, boxed
       comments are defined as those in which the initial ‘/*’ is followed
       immediately by the character ‘*’, ‘=’, ‘_’, or ‘-’, or those in which
       the beginning comment delimiter (‘/*’) is on a line by itself, and
       the following line begins with a ‘*’ in the same column as the star
       of the opening delimiter.

       Examples of boxed comments are:

            /**********************
             * Comment in a box!! *
             **********************/

                   /*
                    * A different kind of scent,
                    * for a different kind of comment.
                    */

       indent  attempts to leave boxed comments exactly as they are found in
       the source file.  Thus the indentation of the comment  is  unchanged,
       and  its  length is not checked in any way.  The only alteration made
       is  that  an  embedded  tab  character  may  be  converted  into  the
       appropriate number of spaces.

       If  the  ‘-bbb’  option is specified, all such boxed comments will be
       preceded by a blank line, unless such a comment is preceded by code.

       Comments which are not boxed comments may be formatted,  which  means
       that  the line is broken to fit within a right margin and left-filled
       with whitespace.  Single newlines are  equivalent  to  a  space,  but
       blank  lines  (two  or  more  newlines  in a row) are taken to mean a
       paragraph break.  Formatting of comments which begin after the  first
       column  is enabled with the ‘-fca’ option.  To format those beginning
       in column one,  specify  ‘-fc1’.   Such  formatting  is  disabled  by
       default.

       The  right  margin  for formatting defaults to 78, but may be changed
       with the ‘-lc’ option.  If the margin specified does  not  allow  the
       comment  to be printed, the margin will be automatically extended for
       the duration of that comment.  The margin is  not  respected  if  the
       comment is not being formatted.

       If  the  ‘-fnc’  option is specified, all comments with ‘/*’ embedded
       will have that character sequence replaced by a space followed by the
       character ‘*’ thus eliminating nesting.

       If  the  comment begins a line (i.e., there is no program text to its
       left), it will be indented to the column it was found in  unless  the
       comment is within a block of code.  In that case, such a comment will
       be aligned with the indented code of that block (unless  the  comment
       began  in  the  first column).  This alignment may be affected by the
       ‘-d’ option, which specifies an amount by  which  such  comments  are
       moved to the left, or unindented.  For example, ‘-d2’ places comments
       two spaces to the left of code.  By  default,  comments  are  aligned
       with  code, unless they begin in the first column, in which case they
       are left there by default --- to get  them  aligned  with  the  code,
       specify ‘-fc1’.

       Comments  to  the  right of code will appear by default in column 33.
       This may be changed with one of three options.  ‘-c’ will specify the
       column  for  comments  following code, ‘-cd’ specifies the column for
       comments following declarations, and ‘-cp’ specifies the  column  for
       comments  following  preprocessor  directives #else and #endif. ‘-dj’
       together with ‘-cd0’ can be used to suppress alignment of comments to
       the  right of declarations, causing the comment to follow one tabstop
       from the end of the  declaration.  Normally  ‘-cd0’  causes  ‘-c’  to
       become effective.

       If  the code to the left of the comment exceeds the beginning column,
       the comment column will be extended to the next tabstop  column  past
       the  end  of  the code, or in the case of preprocessor directives, to
       one space past the end of the directive.  This extension  lasts  only
       for the output of that particular comment.

       The  ‘-cdb’  option  places  the  comment  delimiters on blank lines.
       Thus, a single line comment like /* Loving hug */ can be  transformed
       into:

            /*
               Loving hug
             */

       Stars  can be placed at the beginning of multi-line comments with the
       ‘-sc’ option.  Thus, the single-line comment above can be transformed
       (with ‘-cdb -sc’) into:

            /*
             * Loving hug
             */

STATEMENTS         top

       The ‘-br’ or ‘-bl’ option specifies how to format braces.

       The ‘-br’ option formats statement braces like this:

            if (x > 0) {
              x--;
            }

       The ‘-bl’ option formats them like this:

            if (x > 0)
              {
                x--;
              }

       If  you use the ‘-bl’ option, you may also want to specify the ‘-bli’
       option.  This option specifies the number of spaces by  which  braces
       are  indented.   ‘-bli2’,  the default, gives the result shown above.
       ‘-bli0’ results in the following:

            if (x > 0)
            {
              x--;
            }

       If you are using the ‘-br’ option, you probably want to also use  the
       ‘-ce’  option.   This causes the else in an if-then-else construct to
       cuddle up to the immediately preceding ‘}’.  For example,  with  ‘-br
       -ce’ you get the following:

            if (x > 0) {
              x--;
            } else {
              fprintf (stderr, "...something wrong?\n");
            }

       With ‘-br -nce’ that code would appear as

            if (x > 0) {
              x--;
            }
            else {
              fprintf (stderr, "...something wrong?\n");
            }

       An  exception  to the behavior occurs when there is a comment between
       the right brace and the subsequent else statement.  While  the  ‘-br’
       option  will  cause  a  left brace to jump over the comment, the else
       does not jump over the comment to cuddle  because  it  has  a  strong
       likelihood of changing the meaning of the comment.

       The ‘-cdw’ option causes the while in a do-while loop to cuddle up to
       the immediately preceding ‘}’.  For example, with ‘-cdw’ you get  the
       following:

            do {
              x--;
            } while (x);

       With ‘-ncdw’ that code would appear as

            do {
              x--;
            }
            while (x);

       The  ‘-cli’  option  specifies  the number of spaces that case labels
       should be indented to the right of the containing switch statement.

       The default gives code like:

            switch (i)
              {
              case 0:
                break;
              case 1:
                {
                  ++i;
                }
              default:
                break;
              }

       Using the ‘-cli2’ that would become:

            switch (i)
              {
                case 0:
                  break;
                case 1:
                  {
                    ++i;
                  }
                default:
                  break;
              }

       The  indentation  of  the  braces  below  a  case  statement  can  be
       controlled with the ‘-cbin’ option.  For example, using ‘-cli2 -cbi0’
       results in:

            switch (i)
              {
                case 0:
                  break;
                case 1:
                {
                  ++i;
                }
                default:
                  break;
              }

       If a semicolon is on the same line as a for or while  statement,  the
       ‘-ss’  option  will  cause a space to be placed before the semicolon.
       This emphasizes the semicolon, making it clear that the body  of  the
       for  or  while statement is an empty statement.  ‘-nss’ disables this
       feature.

       The ‘-pcs’ option causes a space to be placed between the name of the
       procedure  being  called and the ‘(’ (for example, puts ("Hi");.  The
       ‘-npcs’ option would give puts("Hi");).

       If the ‘-cs’ option is specified, indent puts a space between a  cast
       operator  and the object to be cast. The ‘-ncs’ ensures that there is
       no space between the cast operator  and  the  object.  Remember  that
       indent  only  knows  about  the  standard  C data types and so cannot
       recognise user-defined types in  casts.  Thus  (mytype)thing  is  not
       treated as a cast.

       The  ‘-bs’  option  ensures that there is a space between the keyword
       sizeof and its argument.  In some versions,  this  is  known  as  the
       ‘Bill_Shannon’ option.

       The  ‘-saf’  option  forces  a  space between a for and the following
       parenthesis.  This is the default.

       The ‘-sai’ option forces a space  between  a  if  and  the  following
       parenthesis.  This is the default.

       The  ‘-saw’  option  forces a space between a while and the following
       parenthesis.  This is the default.

       The ‘-prs’ option causes all parentheses to be separated with a space
       from  whatever is between them.  For example, using ‘-prs’ results in
       code like:

              while ( ( e_code - s_code ) < ( dec_ind - 1 ) )
                {
                  set_buf_break ( bb_dec_ind );
                  *e_code++ = ’ ’;
                }

DECLARATIONS         top

       By default indent will line up identifiers, in the column specified
       by the ‘-di’ option.  For example, ‘-di16’ makes things look like:

            int             foo;
            char           *bar;

       Using  a small value (such as one or two) for the ‘-di’ option can be
       used to cause the identifiers to be placed  in  the  first  available
       position; for example:

            int foo;
            char *bar;

       The value given to the ‘-di’ option will still affect variables which
       are put on separate lines from their types, for example  ‘-di2’  will
       lead to:

            int
              foo;

       If  the  ‘-bc’  option  is  specified, a newline is forced after each
       comma in a declaration.  For example,

            int a,
              b,
              c;

       With the ‘-nbc’ option this would look like

            int a, b, c;

       The ‘-bfda’ option causes a newline to  be  forced  after  the  comma
       separating  the  arguments  of a function declaration.  The arguments
       will  appear  at  one  indention  level  deeper  than  the   function
       declaration.   This  is  particularly helpful for functions with long
       argument lists.  The option ‘-bfde’ causes a  newline  to  be  forced
       before  the  closing  bracket  of  the function declaration. For both
       options the ’n’ setting is the default: -nbdfa and -nbdfe.

       For example,

            void foo (int arg1, char arg2, int *arg3, long arg4, char arg5);
       With the ‘-bfda’ option this would look like

            void foo (
                int arg1,
                char arg2,
                int *arg3,
                long arg4,
                char arg5);

       With, in addition, the ‘-bfde’ option this would look like

            void foo (
                int arg1,
                char arg2,
                int *arg3,
                long arg4,
                char arg5
                );

       The ‘-psl’ option causes the type of a procedure being defined to  be
       placed  on  the line before the name of the procedure.  This style is
       required for the etags program to work correctly, as well as some  of
       the c-mode functions of Emacs.

       You  must  use  the  ‘-T’  option  to tell indent the name of all the
       typenames in your program that are defined by typedef.  ‘-T’  can  be
       specified  more  than  once,  and  all names specified are used.  For
       example, if your program contains

            typedef unsigned long CODE_ADDR;
            typedef enum {red, blue, green} COLOR;

       you would use the options ‘-T CODE_ADDR -T COLOR’.

       The ‘-brs’ or ‘-bls’ option specifies how to format braces in  struct
       declarations.  The ‘-brs’ option formats braces like this:

            struct foo {
              int x;
            };

       The ‘-bls’ option formats them like this:

            struct foo
            {
              int x;
            };

       Similarly to the structure brace ‘-brs’ and ‘-bls’ options,
        the  function  brace  options ‘-brf’ or ‘-blf’ specify how to format
       the braces in function definitions.  The ‘-brf’ option formats braces
       like this:

            int one(void) {
              return 1;
            };

       The ‘-blf’ option formats them like this:

            int one(void)
            {
              return 1;
            };

INDENTATION         top

       One issue in the formatting of code is how far each line should be
       indented from the left margin.  When the beginning of a statement
       such as if or for is encountered, the indentation level is increased
       by the value specified by the ‘-i’ option.  For example, use ‘-i8’ to
       specify an eight character indentation for each level.  When a
       statement is broken across two lines, the second line is indented by
       a number of additional spaces specified by the ‘-ci’ option.  ‘-ci’
       defaults to 0.  However, if the ‘-lp’ option is specified, and a line
       has a left parenthesis which is not closed on that line, then
       continuation lines will be lined up to start at the character
       position just after the left parenthesis.  This processing also
       applies to ‘[’ and applies to ‘{’ when it occurs in initialization
       lists.  For example, a piece of continued code might look like this
       with ‘-nlp -ci3’ in effect:

              p1 = first_procedure (second_procedure (p2, p3),
                 third_procedure (p4, p5));

       With ‘-lp’ in effect the code looks somewhat clearer:

              p1 = first_procedure (second_procedure (p2, p3),
                                    third_procedure (p4, p5));

       When a statement is broken in between two or more paren pairs  (...),
       each extra pair causes the indentation level extra indentation:

            if ((((i < 2 &&
                    k > 0) || p == 0) &&
                q == 1) ||
              n = 0)

       The option ‘-ipN’ can be used to set the extra offset per paren.  For
       instance, ‘-ip0’ would format the above as:

            if ((((i < 2 &&
              k > 0) || p == 0) &&
              q == 1) ||
              n = 0)

       indent assumes that tabs are placed  at  regular  intervals  of  both
       input and output character streams.  These intervals are by default 8
       columns wide, but (as of version 1.2) may be  changed  by  the  ‘-ts’
       option.  Tabs are treated as the equivalent number of spaces.

       The   indentation   of   type   declarations  in  old-style  function
       definitions is controlled by the ‘-ip’ parameter.  This is a  numeric
       parameter  specifying  how  many  spaces to indent type declarations.
       For example, the default ‘-ip5’ makes definitions look like this:

            char *
            create_world (x, y, scale)
                 int x;
                 int y;
                 float scale;
            {
              . . .
            }

       For compatibility with other versions of indent, the option ‘-nip’ is
       provided, which is equivalent to ‘-ip0’.

       ANSI  C allows white space to be placed on preprocessor command lines
       between the character ‘#’ and the command name.  By  default,  indent
       removes  this  space, but specifying the ‘-lps’ option directs indent
       to leave this space unmodified. The option ‘-ppi’ overrides   ‘-nlps’
       and  ‘-lps’.

       This  option  can  be  used  to request that preprocessor conditional
       statements can be indented by to given number of spaces, for  example
       with the option ‘-ppi 3’

            #if X
            #if Y
            #define Z 1
            #else
            #define Z 0
            #endif
            #endif
       becomes
            #if X
            #   if Y
            #      define Z 1
            #   else
            #      define Z 0
            #   endif
            #endif

       This  option  sets  the  offset at which a label (except case labels)
       will be positioned. If it is set to zero or a positive  number,  this
       indicates  how  far from the left margin to indent a label.  If it is
       set to a negative number,  this  indicates  how  far  back  from  the
       current  indent  level to place the label.  The default setting is -2
       which matches the behaviour of earlier versions of indent.  Note that
       this  parameter  does  not affect the placing of case labels; see the
       ‘-cli’ parameter for that. For example with the option ‘-il 1’

            group
            function()
            {
                if (do_stuff1() == ERROR)
                    goto cleanup1;

                if (do_stuff2() == ERROR)
                    goto cleanup2;

                return SUCCESS;

              cleanup2:
                do_cleanup2();

              cleanup1:
                do_cleanup1();

                return ERROR;
            }
       becomes
            group
            function()
            {
                if (do_stuff1() == ERROR)
                    goto cleanup1;

                if (do_stuff2() == ERROR)
                    goto cleanup2;

                return SUCCESS;

             cleanup2:
                do_cleanup2();

             cleanup1:
                do_cleanup1();

                return ERROR;
            }

BREAKING LONG LINES         top

       With the option ‘-ln’, or ‘--line-lengthn’, it is possible to specify
       the maximum length of a line of C code, not including possible
       comments that follow it.

       When lines become longer than the specified line length, GNU indent
       tries to break the line at a logical place.  This is new as of
       version 2.1 however and not very intelligent or flexible yet.

       Currently there are three options that allow one to interfere with
       the algorithm that determines where to break a line.

       The ‘-bbo’ option causes GNU indent to prefer to break long lines
       before the boolean operators && and ||.  The ‘-nbbo’ option causes
       GNU indent not have that preference.  For example, the default option
       ‘-bbo’ (together with ‘--line-length60’ and ‘--ignore-newlines’)
       makes code look like this:

              if (mask
                  && ((mask[0] == ’\0’)
                      || (mask[1] == ’\0’
                          && ((mask[0] == ’0’) || (mask[0] == ’*’)))))

       Using the option ‘-nbbo’ will make it look like this:

              if (mask &&
                  ((mask[0] == ’\0’) ||
                   (mask[1] == ’\0’ &&
                    ((mask[0] == ’0’) || (mask[0] == ’*’)))))

       The  default  ‘-hnl’,  however, honours newlines in the input file by
       giving them the highest possible priority to  break  lines  at.   For
       example, when the input file looks like this:

              if (mask
                  && ((mask[0] == ’\0’)
                  || (mask[1] == ’\0’ && ((mask[0] == ’0’) || (mask[0] == ’*’)))))

       then  using  the option ‘-hnl’, or ‘--honour-newlines’, together with
       the previously mentioned ‘-nbbo’ and  ‘--line-length60’,  will  cause
       the  output  not  to be what is given in the last example but instead
       will prefer to break at the positions where the code  was  broken  in
       the input file:

              if (mask
                  && ((mask[0] == ’\0’)
                      || (mask[1] == ’\0’ &&
                          ((mask[0] == ’0’) || (mask[0] == ’*’)))))

       The idea behind this option is that lines which are too long, but are
       already broken up, will not be touched by GNU indent.   Really  messy
       code  should be run through indent at least once using the ‘--ignore-
       newlines’ option though.

       The ‘-gts’ option affects how the gettext  standard  macros  _()  and
       N_()  are  treated.   The  default  behavior  (or the use of ‘-ngts’)
       causes indent to treat them as it does other  functions,  so  that  a
       long string is broken like the following example.

              if (mask)
                {
                  warning (_
                           ("This is a long string that stays together."));
                }

       With  the  ‘-gts’  option, the underscore is treated as a part of the
       string, keeping it tied to the string, and respecting the  fact  that
       gettext  is  unobtrusively  providing  a localized string.  This only
       works if _(" is together as a unit at the beginning of the string and
       ") is together as a unit at the end.

              if (mask)
                {
                  warning
                    (_("This is a long string that stays together."));
                }

DISABLING FORMATTING         top

       Formatting of C code may be disabled for portions of a program by
       embedding special control comments in the program.  To turn off
       formatting for a section of a program, place the disabling control
       comment /* *INDENT-OFF* */ on a line by itself just before that
       section.  Program text scanned after this control comment is output
       precisely as input with no modifications until the corresponding
       enabling comment is scanned on a line by itself.  The disabling
       control comment is /* *INDENT-ON* */, and any text following the
       comment on the line is also output unformatted.  Formatting begins
       again with the input line following the enabling control comment.

       More precisely, indent does not attempt to verify the closing
       delimiter (*/) for these C comments, and any whitespace on the line
       is totally transparent.

       These control comments also function in their C++ formats, namely //
       *INDENT-OFF* and // *INDENT-ON*.

       It should be noted that the internal state of indent remains
       unchanged over the course of the unformatted section.  Thus, for
       example, turning off formatting in the middle of a function and
       continuing it after the end of the function may lead to bizarre
       results.  It is therefore wise to be somewhat modular in selecting
       code to be left unformatted.

       As a historical note, some earlier versions of indent produced error
       messages beginning with *INDENT**.  These versions of indent were
       written to ignore any input text lines which began with such error
       messages.  I have removed this incestuous feature from GNU indent.

MISCELLANEOUS OPTIONS         top

       To find out what version of indent you have, use the command indent
       -version. This will report the version number of indent, without
       doing any of the normal processing.

       The ‘-v’ option can be used to turn on verbose mode.  When in verbose
       mode, indent reports when it splits one line of input into two more
       more lines of output, and gives some size statistics at completion.

       The ‘-pmt’ option causes indent to preserve the access and
       modification times on the output files.  Using this option has the
       advantage that running indent on all source and header files in a
       project won’t cause make to rebuild all targets.  This option is only
       available on Operating Systems that have the POSIX utime(2) function.

BUGS         top

       Please report any bugs to bug-indent@gnu.org.

       When indent is run twice on a file, with the same profile, it should
       never change that file the second time.  With the current design of
       indent, this can not be guaranteed, and it has not been extensively
       tested.

       indent does not understand C. In some cases this leads to the
       inability to join lines.  The result is that running a file through
       indent is irreversible, even if the used input file was the result of
       running indent with a given profile (‘.indent.pro’).

       While an attempt was made to get indent working for C++, it will not
       do a good job on any C++ source except the very simplest.

       indent does not look at the given ‘--line-length’ option when writing
       comments to the output file.  This results often in comments being
       put far to the right.  In order to prohibit indent from joining a
       broken line that has a comment at the end, make sure that the
       comments start on the first line of the break.

       indent does not count lines and comments (see the ‘-v’ option) when
       indent is turned off with /* *INDENT-OFF* */.

       Comments of the form /*UPPERCASE*/ are not treated as comment but as
       an identifier, causing them to be joined with the next line. This
       renders comments of this type useless, unless they are embedded in
       the code to begin with.

COPYRIGHT         top

       The following copyright notice applies to the indent program.  The
       copyright and copying permissions for this manual appear near the
       beginning of ‘indent.texinfo’ and ‘indent.info’, and near the end of
       ‘indent.1’.

       Copyright (c) 2001 David Ingamells.
       Copyright (c) 1999 Carlo Wood.
       Copyright (c) 1995, 1996 Joseph Arceneaux.
       Copyright (c) 1989, 1992, 1993, 1994, 1995, 1996, 2014 Free Software Foundation
       Copyright (c) 1985 Sun Microsystems, Inc.
       Copyright (c) 1980 The Regents of the University of California.
       Copyright (c) 1976 Board of Trustees of the University of Illinois.
       All rights reserved.

       Redistribution and use in source and binary forms are permitted
       provided that the above copyright notice and this paragraph are
       duplicated in all such forms and that any documentation,
       advertising materials, and other materials related to such
       distribution and use acknowledge that the software was developed
       by the University of California, Berkeley, the University of Illinois,
       Urbana, and Sun Microsystems, Inc.  The name of either University
       or Sun Microsystems may not be used to endorse or promote products
       derived from this software without specific prior written permission.
       THIS SOFTWARE IS PROVIDED ‘‘AS IS’’ AND WITHOUT ANY EXPRESS OR
       IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
       WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
       PURPOSE.

Options’ Cross Key         top

       Here is a list of options alphabetized by long option, to help you
       find the corresponding short option.

            --blank-lines-after-commas                      -bc
            --blank-lines-after-declarations                -bad
            --blank-lines-after-procedures                  -bap
            --blank-lines-before-block-comments             -bbb
            --braces-after-if-line                          -bl
            --braces-after-func-def-line                    -blf
            --brace-indent                                  -bli
            --braces-after-struct-decl-line                 -bls
            --braces-on-if-line                             -br
            --braces-on-func-def-line                       -brf
            --braces-on-struct-decl-line                    -brs
            --break-after-boolean-operator                  -nbbo
            --break-before-boolean-operator                 -bbo
            --break-function-decl-args                      -bfda
            --break-function-decl-args-end                  -bfde
            --case-indentation                              -clin
            --case-brace-indentation                        -cbin
            --comment-delimiters-on-blank-lines             -cdb
            --comment-indentation                           -cn
            --continuation-indentation                      -cin
            --continue-at-parentheses                       -lp
            --cuddle-do-while                               -cdw
            --cuddle-else                                   -ce
            --declaration-comment-column                    -cdn
            --declaration-indentation                       -din
            --dont-break-function-decl-args                 -nbfda
            --dont-break-function-decl-args-end             -nbfde
            --dont-break-procedure-type                     -npsl
            --dont-cuddle-do-while                          -ncdw
            --dont-cuddle-else                              -nce
            --dont-format-comments                          -nfca
            --dont-format-first-column-comments             -nfc1
            --dont-line-up-parentheses                      -nlp
            --dont-left-justify-declarations                -ndj
            --dont-space-special-semicolon                  -nss
            --dont-star-comments                            -nsc
            --else-endif-column                             -cpn
            --format-all-comments                           -fca
            --format-first-column-comments                  -fc1
            --gnu-style                                     -gnu
            --honour-newlines                               -hnl
            --ignore-newlines                               -nhnl
            --ignore-profile                                -npro
            --indent-label                                  -iln
            --indent-level                                  -in
            --k-and-r-style                                 -kr
            --leave-optional-blank-lines                    -nsob
            --leave-preprocessor-space                      -lps
            --left-justify-declarations                     -dj
            --line-comments-indentation                     -dn
            --line-length                                   -ln
            --linux-style                                   -linux
            --no-blank-lines-after-commas                   -nbc
            --no-blank-lines-after-declarations             -nbad
            --no-blank-lines-after-procedures               -nbap
            --no-blank-lines-before-block-comments          -nbbb
            --no-comment-delimiters-on-blank-lines          -ncdb
            --no-space-after-casts                          -ncs
            --no-parameter-indentation                      -nip
            --no-space-after-for                    -nsaf
            --no-space-after-function-call-names            -npcs
            --no-space-after-if                -nsai
            --no-space-after-parentheses                    -nprs
            --no-space-after-while                  -nsaw
            --no-tabs                                       -nut
            --no-verbosity                                  -nv
            --original                                      -orig
            --parameter-indentation                         -ipn
            --paren-indentation                             -pin
            --preserve-mtime                   -pmt
            --preprocessor-indentation                      -ppin
            --procnames-start-lines                         -psl
            --space-after-cast                              -cs
            --space-after-for                  -saf
            --space-after-if                   -sai
            --space-after-parentheses                       -prs
            --space-after-procedure-calls                   -pcs
            --space-after-while                -saw
            --space-special-semicolon                       -ss
            --standard-output                               -st
            --start-left-side-of-comments                   -sc
            --struct-brace-indentation                      -sbin
            --swallow-optional-blank-lines                  -sob
            --tab-size                                      -tsn
            --use-tabs                                      -ut
            --verbose                                       -v

RETURN VALUE         top

       Unknown

FILES         top

       $HOME/.indent.pro   holds default options for indent.

AUTHORS         top

       Carlo Wood
       Joseph Arceneaux
       Jim Kingdon
       David Ingamells

HISTORY         top

       Derived from the UCB program "indent".

COPYING         top

       Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 2014 Free Software
       Foundation, Inc.  Copyright (C) 1995, 1996 Joseph Arceneaux.
       Copyright (C) 1999 Carlo Wood.  Copyright (C) 2001 David Ingamells.
       Copyright (C) 2013 Łukasz Stelmach.

       Permission is granted to make and distribute verbatim copies of this
       manual provided the copyright notice and this permission notice are
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