50. POSIX (POS)

This appendix contains guidelines for functions that are defined as part of the POSIX family of standards but are not included in ISO/IEC 9899-1999. These rules and recommendations are not part of the core standard because they do not apply in all C language applications and because they represent an incomplete set. The intent of providing these guidelines is to demonstrate how rules and recommendations for other standards or specific implementations may be integrated with the core C99 recommendations.

Recommendations

POS00-C. Avoid race conditions with multiple threads

POS01-C. Check for the existence of links when dealing with files

POS02-C. Follow the principle of least privilege

POS03-C. Do not use volatile as a synchronization primitive

Rules

POS30-C. Use the readlink() function properly

POS31-C. Do not unlock or destroy another thread's mutex

POS32-C. When data must be accessed by multiple threads, provide a mutex and guarantee no adjacent data is also accessed.

POS33-C. Do not use vfork()

POS34-C. Do not call putenv() with a pointer to an automatic variable as the argument

POS35-C. Avoid race conditions while checking for the existence of a symbolic link

POS36-C. Observe correct revocation order while relinquishing privileges

POS37-C. Ensure that privilege relinquishment is successful

POS38-C. Be careful when using fork and file descriptors

POS39-C. Use the correct byte ordering when transferring data between systems

Risk Assessment

Related Rules and Recommendations

MSC32-C. Ensure your random number generator is properly seeded      CERT C Secure Coding Standard      POS00-C. Avoid race conditions with multiple threads