Unix Threads Interview Question:

When should we use thread-safe "_r" library calls?

Submitted by: Administrator

If your system provides threads, it will probably provide a
set of thread-safe variants of standard C library routines.
A small number of these are mandated by the POSIX standard,
and many Unix vendors provide their own useful supersets,
including functions such as gethostbyname_r().
Unfortunately, the supersets that different vendors support
do not necessarily overlap, so you can only safely use the
standard POSIX-mandated functions. The thread-safe routines
are conceptually "cleaner" than their stateful
counterparts, though, so it is good practice to use them
wherever and whenever you can.
Submitted by: Administrator