INDENT(1) BSD Reference Manual INDENT(1)
indent - indent and format C program source
indent [input-file [output-file]] [-bad | -nbad] [-bap | -nbap]
[-bbb | -nbbb] [-bc | -nbc] [-bl | -br] [-bs | -nbs] [-cn] [-cdn]
[-cdb | -ncdb] [-ce | -nce] [-cin] [-clin] [-csp | -ncsp] [-dn]
[-din] [-dj | -ndj] [-ei | -nei] [-fc1 | -nfc1] [-in] [-ip | -nip]
[-ln] [-lcn] [-lp | -nlp] [-lpi | -nlpi] [-npro] [-pcs | -npcs]
[-psl | -npsl] [-sc | -nsc] [-sob | -nsob] [-st] [-Ttypename]
[-troff] [-v | -nv]
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
file.BAK exists, it is overwritten.
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. Note: This option
currently has no effect.
-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 -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 Enables (disables) Bill Shannon mode, in which the sizeof
keyword is always followed by a space.
-cn The column in which comments on code start. The default
is 33.
If the option -c0 is used, comments are not touched if
possible.
-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
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 ex-
tra 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.
-csp, -ncsp Enables (disables) space after cast. The default is -csp.
-dn Controls the placement of comments which are not to the
right of code. Specifying -d1 means that such comments
are placed one indentation level to the left of code. The
default, -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. The default is
-ei.
-fc1, -nfc1 Enables (disables) the formatting of comments that start
in column 1. Often, comments whose leading '/' is in
column 1 have been carefully 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 de-
fault is 8.
-ip, -nip Enables (disables) the indentation of parameter declara-
tions from the left margin. The default is -ip. Note:
This option currently has no effect.
-ln Maximum length of an output line. The default is 75.
Note: This option currently has no effect.
-lcn Specify a column width for comments.
-lp, -nlp Lines up code surrounded by parentheses in continuation
lines. If 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. 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));
The default is -lp.
-lpi, -nlpi When -lpi is in effect (default), the continued lines
generated with -nlp are offset by a multiple (the
parenthesis level) of the default continuation indention
set with -ci, else only the basic continuation indention
is used. Caveat: if the option -lp is in effect (de-
fault), the value of this option is being ignored.
The default is -lpi.
-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 ('*') 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. Note: This option currently
has no effect.
-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 accumu-
late: -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. A symptom of missing typedef key-
words is having an extra space after an asterisk in a
code fragment such as:
int foo(char *bar, FILE * baz);
The same code formats nicely, adding -TFILE:
int foo(char *bar, FILE *baz);
This sounds like a painful thing to have to do, but it's
really a symptom of a problem in C: typedef causes a syn-
tactic 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. An .indent.pro file 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.
'Box' comments. indent assumes that any comment with a dash, star, or
newline immediately after the start of comment (that is, '/*-', '/**', or
'/*' followed immediately by a newline character) 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 inden-
tation 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.
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 automat-
ically extended in extreme cases.
In general, indent leaves preprocessor lines alone. The only reformatting
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 peculiari-
ties introduced.
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.
HOME Used to locate the full path to ~/.indent.pro.
./.indent.pro profile file
~/.indent.pro profile file
The indent command appeared in 4.2BSD.
indent has even more switches than ls(1).
A common mistake is to try to indent all the C programs in a directory by
typing:
$ indent *.c
This is probably a bug, not a feature.
MirBSD #10-current March 29, 2014 4