INDENT(1)

NAME
indent - indent and format C program source

SYNOPSIS
indent [ input-file [ output-file ] ] [ -bad | -nbad ] [ -bap | -nbap ] [ -bbb | -nbbb ] [ -bc | -nbc ] [ -bl ] [ -br ] [ -brr ] [ -cn ] [ -cdn ] [ -cdb | -ncdb ] [ -ce | -nce ] [ -cin ] [ -clin ] [ -ccin ] [ -dn ] [ -din ] [ -fc1 | -nfc1 ] [ -in ] [ -ip | -nip ] [ -ln ] [ -lcn ] [ -lp | -nlp ] [ -pcs | -npcs ] [ -npro ] [ -prs | -nprs ] [ -psl | -npsl ] [ -sc | -nsc ] [ -sob | -nsob ] [ -st ] [ -troff ] [ -v | -nv ] [ -+ ]

DESCRIPTION
Indent is a C program formatter. It reformats the C program in the input-file according to the switches. The switches which can be specified are described below. They may appear before or after the file names.

NOTE: If you only specify an input-file, the formatting is done `in-place', that is, the formatted file is written back into input-file and a backup copy of input-file is written in the current directory. If input-file is named `/blah/blah/file', the backup file is named file.BAK.

If output-file is specified, indent checks to make sure it is different from input-file.

OPTIONS

The options listed below control the formatting style imposed by indent.

-bap,-nbap
    If -bap is specified, a blank line is forced after every procedure body. Default: -nbap.

-bad,-nbad
    If -bad is specified, a blank line is forced after every block of declarations. Default: -nbad.

-bbb,-nbbb
    If -bbb is specified, a blank line is forced before every block comment. Default: -nbbb.

-bc,-nbc
    If -bc is specified, then a newline is forced after each comma in a declaration. -nbc turns off this option. The default is -bc.

-br,-bl,-brr
    Specifying -bl lines up compound statements like this:
        if (...)
        {
            code
        }
    Specifying -br (the default) makes them look like this:
        if (...) {
            code
        }
    And specifying -brr makes them look like this:
        if (...)
            {
            code
            }

-cn The column in which comments on code start. The default is 33.

-cdn
    The column in which comments on declarations start. The default is for these comments to start in the same column as those on code.

-cdb,-ncdb
    Enables (disables) the placement of comment delimiters on blank lines. With this option enabled, comments look like this:
    	/*
    	 * this is a comment
    	 */
    Rather than like this:
    	/* this is a comment */
    This only affects block comments, not comments to the right of code. The default is -cdb .

-ce,-nce
    Enables (disables) forcing `else's to cuddle up to the immediatly preceeding `}'. The default is -ce .

-cin
    Sets the continuation indent to be n. Continuation lines will be indented that far from the beginning of the first line of the statement. Parenthesized expressions have extra indentation added to indicate the nesting, unless -lp is in effect. -ci defaults to the same value as -i.

-clin
    Causes case labels to be indented n tab stops to the right of the containing switch statement. -cli0.5 causes case labels to be indented half a tab stop. The default is -cli0 .

-ccin
    Causes case code to be indented n tab stops to the right of the corresponding case label. -cci0.5 causes case code to be indented half a tab stop. The default is -cci1 .

-dn Controls the placement of comments which are not to the right of code. The default -d1 means that such comments are placed one indentation level to the left of code. Specifying -d0 lines up these comments with the code. See the section on comment indentation below.

-din
    Specifies the indentation, in character positions, from a declaration keyword to the following identifier. The default is -di16 .

-fc1,-nfc1
    Enables (disables) the formatting of comments that start in column 1. Often, comments whose leading `/' is in column 1 have been carefully hand formatted by the programmer. In such cases, -nfc1 should be used. The default is -fc1.

-in The number of spaces for one indentation level. The default is 4.

-ip,-nip
    Enables (disables) the indentation of parameter declarations from the left margin. The default is -ip .

-ln Maximum length of an output line. The default is 75.

-npro
    Causes the profile files, `./.indent.pro' and `~/.indent.pro', to be ignored.

-lp,-nlp
    Lines up code surrounded by parenthesis in continuation lines. If a line has a left paren which is not closed on that line, then continuation lines will be lined up to start at the character position just after the left paren. For example, here is how a piece of continued code looks with -nlp in effect:
        p1 = first_procedure(second_procedure(p2, p3),
            third_procedure(p4, p5));
    With -lp in effect (the default) the code looks somewhat clearer:
        p1 = first_procedure(second_procedure(p2, p3),
                             third_procedure(p4, p5));
    Inserting a couple more newlines we get:
        p1 = first_procedure(second_procedure(p2,
                                              p3),
                             third_procedure(p4,
                                             p5));

-pcs , -npcs
    If true (-pcs) all procedure calls will have a space inserted between the name and the '('. The default is -npcs

-prs , -nprs
    If true (-prs) all parentheses will have a space inserted after the '(' and before the ')'. The default is -nprs

-psl , -npsl
    If true (-psl) the names of procedures being defined are placed in column 1 - their types, if any, will be left on the previous lines. The default is -psl

-sc,-nsc
    Enables (disables) the placement of asterisks (`*'s) at the left edge of all comments.

-sob,-nsob
    If -sob is specified, indent will swallow optional blank lines. You can use this to get rid of blank lines after declarations. Default: -nsob

-st Causes indent to take its input from stdin, and put its output to stdout.

-Ttypename
    Adds typename to the list of type keywords. Names accumulate: -T can be specified more than once. You need to specify all the typenames that appear in your program that are defined by typedefs - nothing will be harmed if you miss a few, but the program won't be formatted as nicely as it should. This sounds like a painful thing to have to do, but it's really a symptom of a problem in C: typedef causes a syntactic change in the language and indent can't find all typedefs.

-troff
    Causes indent to format the program for processing by troff. It will produce a fancy listing in much the same spirit as vgrind. If the output file is not specified, the default is standard output, rather than formatting in place.

-v,-nv
    -v turns on `verbose' mode, -nv turns it off. When in verbose mode, indent reports when it splits one line of input into two or more lines of output, and gives some size statistics at completion. The default is -nv.

-+  turns on support for C++. In c++ mode, :: is permited in identifiers, C++ keywords are supported, and class definition keywords (public, private, etc.) are set in column 2.

FURTHER DESCRIPTION

You may set up your own `profile' of defaults to indent by creating a file called .indent.pro in either your login directory or the current directory and including whatever switches you like. A `.indent.pro' in the current directory takes precedence over the one in your login directory. If indent is run and a profile file exists, then it is read to set up the program's defaults. Switches on the command line, though, always override profile switches. The switches should be separated by spaces, tabs or newlines.

Comments

`Box' comments. Indent assumes that any comment with a dash or star immediately after the start of comment (that is, `/*-' or `/**') is a comment surrounded by a box of stars. Each line of such a comment is left unchanged, except that its indentation may be adjusted to account for the change in indentation of the first line of the comment.

Straight text. All other comments are treated as straight text. Indent fits as many words (separated by blanks, tabs, or newlines) on a line as possible. Blank lines break paragraphs.

Comment indentation

If a comment is on a line with code it is started in the `comment column', which is set by the -cn command line parameter. Otherwise, the comment is started at n indentation levels less than where code is currently being placed, where n is specified by the -dn command line parameter. If the code on a line extends past the comment column, the comment starts further to the right, and the right margin may be automatically extended in extreme cases.

Special Comments

Indent produces and interprets some special comments. When indent cannot parse the source, it prints a message on standard error and inserts a comment into the output of the form
	/**INDENT** ErrorMessage */

Indent interprets several special comments as directives. First, it makes no attempt to format lines containing the error comment described above.

Second, lines of the form:
	/* INDENT OFF */
or
	/* INDENT ON */
disable and re-enable indent formatting. Any amount of whitespace may replace the spaces shown in the examples.

Third, indent allows formatting controls to be included in the source via comments of the form:
	/* INDENT: arg1 arg2 arg3 ... arg4 */
The arguments given are in the same syntax as the command line or profile file. For example:
	/* INDENT: -cli.25 -nfc1 */

Preprocessor lines

In general, indent leaves preprocessor lines alone. The only reformmatting that it will do is to straighten up trailing comments. It leaves imbedded comments alone. Conditional compilation (#ifdef...#endif) is recognized and indent attempts to correctly compensate for the syntactic peculiarites introduced.

C syntax

Indent understands a substantial amount about the syntax of C, but it has a `forgiving' parser. It attempts to cope with the usual sorts of incomplete and misformed syntax. In particular, the use of macros like:
        #define forever for(;;)
is handled properly.

FILES
./.indent.pro    profile file

BUGS
Indent has even more switches than ls. A common mistake that often causes grief is typing:
    indent *.c
to the shell in an attempt to indent all the C programs in a directory. This is probably a bug, not a feature.