GETRUSAGE(2)                BSD System Calls Manual               GETRUSAGE(2)

NAME
     getrusage -- get information about resource utilization

SYNOPSIS
     ##include <>
     ##include <>
     ##define   RUSAGESELF     00
     ##define   RUSAGECHILDREN     -1

     int
     getrusage(int who, struct rusage *rusage);

DESCRIPTION
     Getrusage() returns information describing the resources utilized by the
     current process, or all its terminated child processes.  The who parame-
     ter is either RUSAGESELF or RUSAGECHILDREN.  The buffer to which rusage
     points will be filled in with the following structure:

     struct rusage {
             struct timeval ruutime; /* user time used */
             struct timeval rustime; /* system time used */
             long rumaxrss;          /* integral max resident set size */
             long ruixrss;           /* integral shared text memory size */
             long ruidrss;           /* integral unshared data size */
             long ruisrss;           /* integral unshared stack size */
             long ruminflt;          /* page reclaims */
             long rumajflt;          /* page faults */
             long runswap;           /* swaps */
             long ruinblock;         /* block input operations */
             long ruoublock;         /* block output operations */
             long rumsgsnd;          /* messages sent */
             long rumsgrcv;          /* messages received */
             long runsignals;        /* signals received */
             long runvcsw;           /* voluntary context switches */
             long runivcsw;          /* involuntary context switches */
     };

     The fields are interpreted as follows:

     ruutime     the total amount of time spent executing in user mode.

     rustime     the total amount of time spent in the system executing on
                  behalf of the process(es).

     rumaxrss    the maximum resident set size utilized (in kilobytes).

     ruixrss     an integral value indicating the amount of memory used by
                  the text segment that was also shared among other processes.
                  This value is expressed in units of kilobytes * ticks-of-
                  execution.

     ruidrss     an integral value of the amount of unshared memory residing
                  in the data segment of a process (expressed in units of
                  kilobytes * ticks-of-execution).

     ruisrss     an integral value of the amount of unshared memory residing
                  in the stack segment of a process (expressed in units of
                  kilobytes * ticks-of-execution).

     ruminflt    the number of page faults serviced without any I/O activity;
                  here I/O activity is avoided by reclaiming a page frame from
                  the list of pages awaiting reallocation.

     rumajflt    the number of page faults serviced that required I/O activ-
                  ity.

     runswap     the number of times a process was swapped out of main mem-
                  ory.

     ruinblock   the number of times the file system had to perform input.

     ruoublock   the number of times the file system had to perform output.

     rumsgsnd    the number of IPC messages sent.

     rumsgrcv    the number of IPC messages received.

     runsignals  the number of signals delivered.

     runvcsw     the number of times a context switch resulted due to a
                  process voluntarily giving up the processor before its time
                  slice was completed (usually to await availability of a
                  resource).

     runivcsw    the number of times a context switch resulted due to a
                  higher priority process becoming runnable or because the
                  current process exceeded its time slice.

NOTES
     The numbers ruinblock and ruoublock account only for real I/O; data
     supplied by the caching mechanism is charged only to the first process to
     read or write the data.

ERORS
     Getrusage() returns -1 on error.  The possible errors are:

     [EINVAL]           The who parameter is not a valid value.

     [EFAULT]           The address specified by the rusage parameter is not
                        in a valid part of the process address space.

SEE ALSO
     gettimeofday(2), wait(2)

BUGS
     There is no way to obtain information about a child process that has not
     yet terminated.

HISTORY
     The getrusage() function call appeared in 4.2BSD.

4th Berkeley Distribution        June 4, 1993        4th Berkeley Distribution