• Avoid macros where other alternatives exist
• Only use forward-gotos, and only where it is readable
• Tabs, not spaces.
• surround a binary operator (particular a low precedence
one) with spaces; don't try to write the most compact
code possible but rather the most readable.
• parenthesize expressions involving arithmetic and bit-
wise operators; otherwise don't parenthesize heavily
• no white space before opening braces.
• no white space after the keywords `if', `for', `while',
• no braces around single-line blocks (e.g., `if', `for',
and `while' bodies).
• integer-valued functions return -1 on error, 0 or posi-
tive on success.
• enum or #defined constants should be UPPERCASE.
• automatic variables (local variables inside a function)
are never initialized at declaration.
• follow the standard idioms: use `x < 0' not `0 > x', etc.
• don't write `!strcmp' (nor `!memcmp', etc.) nor
`if(memcmp(a, b, c))'; always explicitly compare the
result of string or memory comparison with zero using a
• One statement should have one effect. Never use e.g. `x[a++] = b`;
use `x[a] = b; a += 1;` instead.
• Don't use prefix or postfix operators (a++ or --a, for instance),
use the assignment forms instead (e.g. `a += 1`).
Ultimately, the goal is to write code that fits in with the
other code around it and the system as a whole. If the file
you are editing already deviates from these guidelines, do
what it does. After you edit a file, a reader should not be
able to tell just from coding style which parts you worked
If your code is readable, you shouldn't need many comments.
A line or two comment above a function explaining what it
does is always welcome.
Comment any code you find yourself wondering about for more
than 2 seconds, even if it's to say that you don't under-
stand what's going on. Explain why.
Don't use commenting as an excuse for writing confusing
code. Rewrite the code to make it clear.
Do the simple thing. Don't optimize unless you've measured
the code and it is too slow. Fix the data structures and
the algorithms instead of going for little 5% tunings.