1. C language source code formatting program The `indent' program changes the appearance of a C program by inserting or deleting whitespace. `indent' also provides options for controlling the alignment of braces and declarations, program indenting, and other stylistic parameters, including formatting of both C and C++ comments. From Debian 3.0r0 APT

2. Indent is a GNU program for formatting C code, so that it is easier to read. Indent can also convert from one C writing style to adifferent one. Indent understands correct C syntax and tries to handle incorrect C syntax. From Redhat 8.0 RPM