rusage

I just noticed this line in the getrusage man page: Including <sys/time.h> is not required these days, but increases portability. (Indeed, struct timeval is defined in <sys/time.h> ) What? Since struct rusage contains struct timeval as a member, surely sys/resource.h must include sys/time.h or the type would be incomplete and unusable? How could this comment ever have made sense? How could it ever have not been necessary? How could portability have ever been helped? In general, it was not uncommon in the early days of C for you to have to manually include header file A before header file B.

I am trying to print a value of type timeval. Actually I am able to print it, but I get the following warning: Multiple markers at this line format ‘%ld’ expects type ‘long int’, but argument 2 has type ‘struct timeval’ The program compiles and it prints the values, but I would like to know if I am doing something wrong. Thanks. printf("%ld.%6ld\n",usage.ru_stime); printf("%ld.%6ld\n",usage.ru_utime); where usage is of type typedef struct{ struct timeval ru_utime; /* user time used */ struct timeval ru_stime; /* system time used */ long ru_maxrss; /* maximum resident set size */ long ru_ixrss;