C library system-call wrappers, or the lack thereof

Posted Nov 14, 2018 22:13 UTC (Wed) by Cyberax (✭ supporter ✭, #52523)
In reply to: C library system-call wrappers, or the lack thereof by dtlin
Parent article: C library system-call wrappers, or the lack thereof

New memcpy_fast can be safely backported and the migration to memcpy_fast can be made over the period of many years. It's also easy to control:

#ifdef API_LEVEL >= 20180101
#define memcpy memcpy_fast
#endif

That's basically how migration to long files went without causing many issues.

C library system-call wrappers, or the lack thereof

Posted Nov 14, 2018 23:24 UTC (Wed) by nybble41 (subscriber, #55106) [Link]

> New memcpy_fast can be safely backported

There is nothing to prevent someone from backporting new versions of select glibc functions into older libraries. It just isn't necessary: If you were to transplant a modern build of glibc into RHEL6 all the old applications would still work, thanks to symbol versioning. Why maintain backports when you can just upgrade glibc?