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SYSINFO(2)		   Linux Programmer's Manual		    SYSINFO(2)



NAME
       sysinfo - return system information

SYNOPSIS
       #include <sys/sysinfo.h>

       int sysinfo(struct sysinfo *info);

DESCRIPTION
       sysinfo()  returns certain statistics on memory and swap usage, as well
       as the load average.

       Until Linux 2.3.16, sysinfo() returned  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 */
	   };

       In  the	above  structure,  the sizes of the memory and swap fields are
       given in bytes.

       Since Linux 2.3.23 (i386) and  Linux  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 to 64 bytes */
	   };

       In  the	above structure, sizes of the memory and swap fields are given
       as multiples of mem_unit bytes.

RETURN VALUE
       On success, sysinfo() returns zero.  On	error,	-1  is	returned,  and
       errno is set to indicate the cause of the error.

ERRORS
       EFAULT info is not a valid address.

VERSIONS
       sysinfo() first appeared in Linux 0.98.pl6.

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

NOTES
       All of the information provided by this system call is  also  available
       via /proc/meminfo and /proc/loadavg.

SEE ALSO
       proc(5)

COLOPHON
       This  page  is  part of release 4.10 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest	  version     of     this    page,    can    be	   found    at
       https://www.kernel.org/doc/man-pages/.



Linux				  2016-07-17			    SYSINFO(2)