#define _REENTRANT #includeYou need to include the pthread library when compiling:
gcc -g -lpthread -D_REENTRANTor, for the Solaris compiler,
cc -mt -lpthread
The program will compile without it, but will exit immediately, with the thread creation routines returning a value of -1.
Be sure to check each thread routine for error return values, in particular if the program isn't working properly. Generally speaking, the thread routines return zero on success and non-zero (-1 or a positive integer) on error. If the return value is a positive integer, see /usr/include/sys/errno.h for the mapping, with the call-specific reasons found on the man page. Use strerror() to convert the error value to a text string, but be careful to only pass it positive values.
Last updated by Henning Schulzrinne