#define _POSIX_SOURCE #define _POSIX_C_SOURCE 199309L #include<stdio.h> #include<unistd.h> int main() { #ifdef _POSIX_JOB_CONTROL printf("System supports job control\n"); #else printf("System does not...

#define _POSIX_SOURCE #define _POSIX_C_SOURCE 199309L #include<stdio.h> #include<unistd.h> int main() { int res; if((res = sysconf(_SC_OPEN_MAX)) == -1) perror("sysconf"); else printf("OPEN_MAX:%d\n",res);...