standards.info: Names

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Naming Variables and Functions

   The names of global variables and functions in a program serve as
comments of a sort.  So don't choose terse names--instead, look for
names that give useful information about the meaning of the variable or
function.  In a GNU program, names should be English, like other
comments.
   Local variable names can be shorter, because they are used only
within one context, where (presumably) comments explain their purpose.
   Please use underscores to separate words in a name, so that the Emacs
word commands can be useful within them.  Stick to lower case; reserve
upper case for macros and `enum' constants, and for name-prefixes that
follow a uniform convention.
   For example, you should use names like `ignore_space_change_flag';
don't use names like `iCantReadThis'.
   Variables that indicate whether command-line options have been
specified should be named after the meaning of the option, not after
the option-letter.  A comment should state both the exact meaning of
the option and its letter.  For example,
     /* Ignore changes in horizontal whitespace (-b).  */
     int ignore_space_change_flag;
   When you want to define names with constant integer values, use
`enum' rather than `#define'.  GDB knows about enumeration constants.
   Use file names of 14 characters or less, to avoid creating gratuitous
problems on older System V systems.  You can use the program `doschk'
to test for this.  `doschk' also tests for potential name conflicts if
the files were loaded onto an MS-DOS file system--something you may or
may not care about.