As of version 1.3, the format of the indent command is:
indent [options] [input-files]
indent [options] [single-input-file] [-o output-file]
This format is different from earlier versions and other versions
of indent.
In the first form, one or more input files are specified. indent
makes a backup copy of each file, and the original file is
replaced with its indented version. See BACKUP FILES, for an
explanation of how backups are made.
In the second form, only one input file is specified. In this
case, or when the standard input is used, you may specify an
output file after the '-o' option.
To cause indent to write to standard output, use the '-st'
option. This is only allowed when there is only one input file,
or when the standard input is used.
If no input files are named, the standard input is read for
input. Also, if a filename named '-' is specified, then the
standard input is read.
As an example, each of the following commands will input the
program 'slithy_toves.c' and write its indented text to
'slithy_toves.out':
indent slithy_toves.c -o slithy_toves.out
indent -st slithy_toves.c > slithy_toves.out
cat slithy_toves.c | indent -o slithy_toves.out
Most other options to indent control how programs are formatted.
As of version 1.2, indent also recognizes a long name for each
option name. Long options are prefixed by either '--' or '+'. [
'+' is being superseded by '--' to maintain consistency with the
POSIX standard.]
In most of this document, the traditional, short names are used
for the sake of brevity. See OPTION SUMMARY, for a list of
options, including both long and short names.
Here is another example:
indent -br test/metabolism.c -l85
This will indent the program 'test/metabolism.c' using the '-br'
and '-l85' options, write the output back to 'test/metabolism.c',
and write the original contents of 'test/metabolism.c' to a
backup file in the directory 'test'.
Equivalent invocations using long option names for this example
would be:
indent --braces-on-if-line --line-length185 test/metabolism.c
indent +braces-on-if-line +line-length185 test/metabolism.c
If you find that you often use indent with the same options, you
may put those options into a file named '.indent.pro'. indent
will look for a profile file in three places. First it will check
the environment variable INDENT_PROFILE. If that exists its value
is expected to name the file that is to be used. If the
environment variable does not exist, indent looks for
'.indent.pro' in the current directory
and use that if found. Finally indent will search your home
directory for '.indent.pro' and use that file if it is found.
This behaviour is different from that of other versions of
indent, which load both files if they both exist.
The format of '.indent.pro' is simply a list of options, just as
they would appear on the command line, separated by white space
(tabs, spaces, and newlines). Options in '.indent.pro' may be
surrounded by C or C++ comments, in which case they are ignored.
Command line switches are handled after processing '.indent.pro'.
Options specified later override arguments specified earlier,
with one exception: Explicitly specified options always override
background options (See COMMON STYLES). You can prevent indent
from reading an '.indent.pro' file by specifying the '-npro'
option.
