procps_misc(3)

NAME#

procps_misc - API for miscellaneous information in the /proc filesystem

SYNOPSIS#

#include <libproc2/misc.h>

Platform Particulars

long         \nprocps_cpu_count\n (void);
long         \nprocps_hertz_get\n (void);
unsigned int \nprocps_pid_length\n (void);
int          \nprocps_linux_version\n (void);

Runtime Particulars

int  \n procps_loadavg\n (double *\nav1\n, double *\nav5\n, double *\nav15\n);
int  \n procps_uptime\n (double *\nuptime_secs\n, double *\nidle_secs\n);
char *\nprocps_uptime_sprint\n (void);
char *\nprocps_uptime_sprint_short\n (void);

Namespace Particulars

int       \n  procps_ns_get_id\n (const char *\nname\n);
const char\n *procps_ns_get_name\n (int \nid\n);
int       \n  procps_ns_read_pid\n (int \npid\n, struct procps_ns *\nnsp\n);

Link with \n-lproc2\n.

DESCRIPTION#

procps_cpu_count() returns the number of CPUs that are currently online as sysconf(_SC_NPROCESSORS_ONLY) or an assumed 1.

procps_hertz_get() returns the number of clock ticks per second as sysconf(_SC_CLK_TCK) or an assumed 100. Dividing tics by this value yields seconds.

procps_pid_length() returns the maximum string length for a PID on the system. For example, if the largest possible PID value on was 123, then the length would be 3. If the file /proc/sys/kernel/pid_max is unreadable, the value is assumed to be 5.

procps_linux_version() returns the current Linux version as an encoded integer. On non-Linux systems that have an emulated proc filesystem this function returns the version of the Linux emulation instead. The version consists of three positive integers representing the major, minor and patch levels. The following macros are provided for encoding a given Linux version or separating out the components of the current version.

LINUX_VERSION( major , minor , patch )

LINUX_VERSION_MAJOR( ver )

LINUX_VERSION_MINOR( ver )

LINUX_VERSION_PATCH( ver )

procps_loadavg() fetches the system load average and puts the 1, 5 and 15 minute averages into location(s) specified by any pointer which is not NULL.

procps_uptime() returns uptime and/or idle seconds into location(s) specified by any pointer which is not NULL. The sprint varieties return a human-readable string in one of two forms.

HH:MM:SS up HH:MM, # users, load average: 1, 5, 15 MM averages

up HH, MM

procps_ns_get_id() returns the integer id (enum namespace_type) of the namespace for the given namespace name.

procps_ns_get_name() returns the name of the namespace for the given id (enum namespace_type).

procps_ns_read_pid() returns the inodes for the namespaces of the given process in the procps_ns structure pointed to by nsp. Those inodes will appear in the order proscribed by enum namespace_type.

enum namespace_type {
\n
    PROCPS_NS_CGROUP,
\n
    PROCPS_NS_IPC,
\n
    PROCPS_NS_MNT,
\n
    PROCPS_NS_NET,
\n
    PROCPS_NS_PID,
\n
    PROCPS_NS_TIME,
\n
    PROCPS_NS_USER,
\n
    PROCPS_NS_UTS
};

RETURN VALUE#

Functions Returning an `int' or `long'#

An error will be indicated by a negative number that is always the inverse of some well known errno.h value.

Functions Returning an `address'#

An error will be indicated by a NULL return pointer with the reason found in the formal errno value.

FILES#

/proc/loadavg

The raw values for load average.

/proc/sys/kernel/osrelease

Contains the release version of the Linux kernel or proc filesystem.

/proc/sys/kernel/pid_max

Contains the value at which PIDs wrap around, one greater than the maximum PID value.

/proc/uptime

The raw values for uptime and idle time.

/proc/<PID>/ns

contains the set of namespaces for a particular PID.

SEE ALSO#

procps(3), procps_pids(3), proc(5).