NAME
indent
—
indent and format C program
source
SYNOPSIS
indent |
[input_file [output_file]]
[-bacc | -nbacc ]
[-bad | -nbad ]
[-bap | -nbap ]
[-bbb | -nbbb ]
[-bc | -nbc ]
[-bl ] [-br ]
[-c n]
[-cd n]
[-cdb | -ncdb ]
[-ce | -nce ]
[-ci n]
[-cli n]
[-d n]
[-di n]
[-ei | -ei ]
[-eei | -eei ]
[-fbs | -nfbs ]
[-fc1 | -nfc1 ]
[-fcb | -nfcb ]
[-i n]
[-ip | -nip ]
[-l n]
[-lc n]
[-ldi n]
[-lp | -nlp ]
[-npro ] [-pcs |
-npcs ] [-psl |
-npsl ] [-sc |
-nsc ]
[-sob | -nsob ]
[-st ] [-ta ]
[-troff ] [-ut |
-nut ] [-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 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. The default is-nbacc
. -bad
,-nbad
- If
-bad
is specified, a blank line is forced after every block of declarations. The default is-nbad
. -bap
,-nbap
- If
-bap
is specified, a blank line is forced after every procedure body. The default is-nbap
. -bbb
,-nbbb
- If
-bbb
is specified, a blank line is forced before every block comment. The default is-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
. -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 of `else's to cuddle up to the immediately
preceding `}'. The default is
-ce
. -ci
n- 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
. -cli
n- 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
. -d
n- 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. -di
n- 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
.-ei
,-nei
- Enables (disables) special
else-if
processing. If it is enabled, anif
following anelse
will have the same indentation as the precedingif
statement. The default is-ei
. -eei
,-neei
- Enables (disables) extra indentation on continuation lines of the
expression part of
if
andwhile
statements. These continuation lines will be indented one extra level. The default is-neei
. -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
. -i
n- The number of spaces 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
. -l
n- Maximum length of an output line. The default is 78.
-ldi
n- 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 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 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. The default is-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.
-T
typename- 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 bytypedef
- 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 andindent
cannot find all instances oftypedef
. -troff
- Causes
indent
to format the program for processing by troff(1). If the output file is not specified, the default is standard output, rather than formatting in place. -ut
,-nut
- Enables (disables) the use of tab characters in the output. Tabs are
assumed to be aligned on columns divisible by 8. 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
.
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.
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
-c
n 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
-d
n 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.
Preprocessor lines
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 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 incomplete 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.