sysinfo(2)

1sysinfo(2)                    System Calls Manual                   sysinfo(2)
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NAME

6       sysinfo - return system information
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LIBRARY

9       Standard C library (libc, -lc)
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SYNOPSIS

12       #include <sys/sysinfo.h>
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14       int sysinfo(struct sysinfo *info);
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DESCRIPTION

17       sysinfo()  returns certain statistics on memory and swap usage, as well
18       as the load average.
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20       Until Linux 2.3.16, sysinfo() returned  information  in  the  following
21       structure:
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23           struct sysinfo {
24               long uptime;             /* Seconds since boot */
25               unsigned long loads[3];  /* 1, 5, and 15 minute load averages */
26               unsigned long totalram;  /* Total usable main memory size */
27               unsigned long freeram;   /* Available memory size */
28               unsigned long sharedram; /* Amount of shared memory */
29               unsigned long bufferram; /* Memory used by buffers */
30               unsigned long totalswap; /* Total swap space size */
31               unsigned long freeswap;  /* Swap space still available */
32               unsigned short procs;    /* Number of current processes */
33               char _f[22];             /* Pads structure to 64 bytes */
34           };
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36       In  the  above  structure,  the sizes of the memory and swap fields are
37       given in bytes.
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39       Since Linux 2.3.23 (i386) and  Linux  2.3.48  (all  architectures)  the
40       structure is:
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42           struct sysinfo {
43               long uptime;             /* Seconds since boot */
44               unsigned long loads[3];  /* 1, 5, and 15 minute load averages */
45               unsigned long totalram;  /* Total usable main memory size */
46               unsigned long freeram;   /* Available memory size */
47               unsigned long sharedram; /* Amount of shared memory */
48               unsigned long bufferram; /* Memory used by buffers */
49               unsigned long totalswap; /* Total swap space size */
50               unsigned long freeswap;  /* Swap space still available */
51               unsigned short procs;    /* Number of current processes */
52               unsigned long totalhigh; /* Total high memory size */
53               unsigned long freehigh;  /* Available high memory size */
54               unsigned int mem_unit;   /* Memory unit size in bytes */
55               char _f[20-2*sizeof(long)-sizeof(int)];
56                                        /* Padding to 64 bytes */
57           };
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59       In  the  above structure, sizes of the memory and swap fields are given
60       as multiples of mem_unit bytes.
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RETURN VALUE

63       On success, sysinfo() returns zero.  On error, -1 is returned, and  er‐
64       rno is set to indicate the error.
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ERRORS

67       EFAULT info is not a valid address.
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STANDARDS

70       Linux.
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HISTORY

73       Linux 0.98.pl6.
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NOTES

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