NAME

indent — indent and format C program source

SYNOPSIS

DESCRIPTION

The indent utility 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’ by default. The extension used for the backup file may be overridden using the SIMPLE_BACKUP_SUFFIX environment variable.

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

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

-bacc, -nbacc

If -bacc is specified, a blank line is forced around every conditional compilation block. For example, in front of every #ifdef and after every #endif. Other blank lines surrounding such blocks will be swallowed. Default: -nbacc.

-bad, -nbad

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

-badp, -nbadp

This is vaguely similar to -bad except that it only applies to the first set of declarations in a procedure (just after the first `{') and it causes a blank line to be generated even if there are no declarations. The default is -nbadp.

-bap, -nbap

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

-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. Default: -nbc.

-bl, -br

Specifying -bl lines up compound statements like this:

if (...)
{
  code
}

Specifying -br (the default) makes them look like this:

if (...) {
  code
}

-bs, -nbs

Whether a blank should always be inserted after sizeof. The default is -nbs.

-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 of `else's to cuddle up to the immediately preceding `}'. 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 or the continuation indent is exactly half of the main indent. -ci defaults to the same value as -i.

-clin

Causes case labels to be indented n indentation levels to the right of the containing switch statement. -cli0.5 causes case labels to be indented half an indentation level. The default is -cli0.

-cs, -ncs

Control whether parenthesized type names in casts are followed by a space or not. The default is -ncs.

-dn

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

-din

Specifies the indentation, in character positions, of global variable names and all struct/union member names relative to the beginning of their type declaration. The default is -di16.

-dj, -ndj

-dj left justifies declarations. -ndj indents declarations the same as code. The default is -ndj.

-eei, -neei

Enables (disables) extra indentation on continuation lines of the expression part of if and while statements. These continuation lines will be indented one extra level. The default is -neei.

-ei, -nei

Enables (disables) special else-if processing. If it is enabled, an if following an else will have the same indentation as the preceding if statement. The default is -ei.

-fbs, -nfbs

Enables (disables) splitting the function declaration and opening brace across two lines. The default is -fbs.

-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.

-fcb, -nfcb

Enables (disables) the formatting of block comments (ones that begin with `/*\n'). Often, block comments have been not so carefully hand formatted by the programmer, but reformatting that would just change the line breaks is not wanted. In such cases, -nfcb should be used. Block comments are then handled like box comments. The default is -fcb.

-in

The number of columns for one indentation level. The default is 8.

-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 78.

-lcn

Maximum length of an output line in a block comment. The default is 0, which means to limit block comment lines in accordance with -l.

-ldin

Specifies the indentation, in character positions, of local variable names relative to the beginning of their type declaration. The default is for local variable names to be indented by the same amount as global ones.

-lp, -nlp

Lines up code surrounded by parentheses in continuation lines. With -lp, 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 two more newlines we get:

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

-lpl, -nlpl

With -lpl, code surrounded by parentheses in continuation lines is lined up even if it would extend past the right margin. With -nlpl (the default), such a line that would extend past the right margin is moved left to keep it within the margin, if that does not require placing it to the left of the prevailing indentation level. These switches have no effect if -nlp is selected.

-npro

Causes the profile files, ‘./.indent.pro’ and ‘~/.indent.pro’, to be ignored.

-Pfile

Read profile from file.

-pcs, -npcs

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

-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. The default is -sc.

-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.

-ta

Automatically add all identifiers ending in "_t" to the list of type keywords.

-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 typedef - nothing will be harmed if you miss a few, but the program will not be formatted as nicely as it should. This sounds like a painful thing to have to do, but it is really a symptom of a problem in C: typedef causes a syntactic change in the language and indent cannot find all instances of typedef.

-tsn

Assumed distance between tab stops. The default is 8.

-Ufile

Adds type names from file to the list of type keywords.

-ut, -nut

Enables (disables) the use of tab characters in the output. The default is -ut.

-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.

--version

Causes indent to print its version number and exit.

You may set up your own `profile' of defaults to indent by creating a file called .indent.pro in your login directory and/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.

ENVIRONMENT

The indent utility uses the HOME environment variable.

FILES

./.indent.pro

profile file

~/.indent.pro

profile file

HISTORY

The indent command appeared in 4.2BSD.

BUGS

The indent utility has even more switches than ls(1).

A common mistake is to try to indent all the C programs in a directory by typing:

This is probably a bug, not a feature.