plucky (3) procps_misc.3.gz

Provided by: procps_4.0.4-4ubuntu5_amd64 bug

NAME

       procps_misc - API for miscellaneous information in the /proc filesystem

SYNOPSIS

       #include <libproc2/misc.h>

       Platform Particulars

           long         procps_cpu_count (void);
           long         procps_hertz_get (void);
           unsigned int procps_pid_length (void);
           int          procps_linux_version (void);

       Runtime Particulars

           int   procps_loadavg (double *av1, double *av5, double *av15);
           int   procps_uptime (double *uptime_secs, double *idle_secs);
           char *procps_uptime_sprint (void);
           char *procps_uptime_sprint_short (void);

       Namespace Particulars

           int         procps_ns_get_id (const char *name);
           const char *procps_ns_get_name (int id);
           int         procps_ns_read_pid (int pid, struct procps_ns *nsp);

       Link with -lproc2.

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 {
               PROCPS_NS_CGROUP,
               PROCPS_NS_IPC,
               PROCPS_NS_MNT,
               PROCPS_NS_NET,
               PROCPS_NS_PID,
               PROCPS_NS_TIME,
               PROCPS_NS_USER,
               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).