INDENT(1) MachTen Reference Manual INDENT(1)

NAME
indent - indent and format C program source

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 speci-
fied 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.

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

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

-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. The
default is -bc.

-br, -bl Specifying -bl lines up compound statements like this:

if (...)
{
code
}

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

if (...) {
code
}

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

-cd -n 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
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. -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.

-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 de-
fault is -di16.

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

-ei, -nei Enables (disables) special else-if processing. If it’s
enabled, an if following an else will have the same in-
dentation as the preceding if statement.

-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 pro-
grammer. In such cases, -nfc1 should be used. The de-
fault is -fc1.

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

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

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

-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 two more newlines we get:

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

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

-pcs, -npcs If true (-pcs) all procedure calls will have a space in-
serted 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.

-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 accu-
mulate: -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 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 instances of typedef.

-troff Causes indent to format the program for processing by
troff(1). It will produce a fancy listing in much the
same spirit as vgrind(1). 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.

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 direc-
tory 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 over-
ride 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 imme-
diately 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 un-
changed, 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 col-
umn’, which is set by the -cn command line parameter. Otherwise, the
comment is started at n indentation levels less than where code is cur-
rently being placed, where n is specified by the -dn command line parame-
ter. 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.

Preprocessor lines
In general, indent leaves preprocessor lines alone. The only reformat-
ting that it will do is to straighten up trailing comments. It leaves
embedded comments alone. Conditional compilation (#ifdef...#endif) is
recognized and indent attempts to correctly compensate for the syntactic
peculiarities 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 incom-
plete and misformed syntax. In particular, the use of macros like:

#define forever for(;;)

is handled properly.

ENVIRONMENT
Indent uses the HOME environment variable.

FILES
./.indent.pro profile file
~/.indent.pro profile file

HISTORY
The indent command appeared in 4.2BSD.

BUGS
Indent has even more switches than ls(1).

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.

4.2 Berkeley Distribution July 1, 1993 4