sysinfo - returns information on overall system statistics


SYNOPSIS

       #include <sys/sysinfo.h>

       int sysinfo(struct sysinfo *info);


DESCRIPTION

       Until Linux 2.3.16, sysinfo used to return information  in
       the following structure:

              struct sysinfo {
                   long uptime;             /* Seconds since boot */
                   unsigned long loads[3];  /* 1, 5, and 15 minute load averages */
                   unsigned long totalram;  /* Total usable main memory size */
                   unsigned long freeram;   /* Available memory size */
                   unsigned long sharedram; /* Amount of shared memory */
                   unsigned long bufferram; /* Memory used by buffers */
                   unsigned long totalswap; /* Total swap space size */
                   unsigned long freeswap;  /* swap space still available */
                   unsigned short procs;    /* Number of current processes */
                   char _f[22];             /* Pads structure to 64 bytes */
              };

       and  the  sizes  were  given  in bytes. Since Linux 2.3.23
       (i386), 2.3.48 (all architectures) the structure is

              struct sysinfo {
                   long uptime;             /* Seconds since boot */
                   unsigned long loads[3];  /* 1, 5, and 15 minute load averages */
                   unsigned long totalram;  /* Total usable main memory size */
                   unsigned long freeram;   /* Available memory size */
                   unsigned long sharedram; /* Amount of shared memory */
                   unsigned long bufferram; /* Memory used by buffers */
                   unsigned long totalswap; /* Total swap space size */
                   unsigned long freeswap;  /* swap space still available */
                   unsigned short procs;    /* Number of current processes */
                   unsigned long totalhigh; /* Total high memory size */
                   unsigned long freehigh;  /* Available high memory size */
                   unsigned int mem_unit;   /* Memory unit size in bytes */
                   char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding for libc5 */
              };

       and the sizes are given as multiples of mem_unit bytes.

       sysinfo provides a simple way of  getting  overall  system
       statistics.  This is more portable than reading /dev/kmem.
       For an example of its use, see intro(2).


RETURN VALUE

       On success, zero is returned.  On error, -1  is  returned,
       and errno is set appropriately.
       EFAULT pointer to struct sysinfo is invalid


CONFORMING TO

       This function is Linux-specific, and should not be used in
       programs intended to be portable.

       The Linux kernel has a sysinfo system call since 0.98.pl6.
       Linux  libc  contains a sysinfo() routine since 5.3.5, and
       glibc has one since 1.90.


SEE ALSO

       proc(5)