docs: adapt procps_misc.3 for new 'misc.h' header file
This commit adapts our man page for a new consolidated 'misc.h' header file. Along the way, some descriptions were shortened, others lengthened and whitespace added in an effort to (hopefully) improve readability a bit. [ the #include subdirectory was also corrected while ] [ rearranging & grouping functions into 3 categories ] Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit is contained in:
parent
423297c9db
commit
baa9dc93f9
@ -1,4 +1,5 @@
|
||||
.\" (C) Copyright 2020 Craig Small <csmall@dropbear.xyz>
|
||||
.\" (C) Copyright 2021 Jim Warner <warnerjc@comcast.net>
|
||||
.\"
|
||||
.\" %%%LICENSE_START(LGPL_2.1+)
|
||||
.\" This manual is free software; you can redistribute it and/or
|
||||
@ -16,169 +17,128 @@
|
||||
.\" Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
.\" %%%LICENSE_END
|
||||
.\"
|
||||
.TH PROCPS_MISC 3 2020-12-21 "libproc-2"
|
||||
.TH PROCPS_MISC 3 "January 2021" "libproc-2"
|
||||
.\" Please adjust this date whenever revising the manpage.
|
||||
.\"
|
||||
.nh
|
||||
.SH NAME
|
||||
procps_misc \- API to system information in the /proc filesystem
|
||||
procps_misc \- API for miscellaneous information in the /proc filesystem
|
||||
.SH SYNOPSIS
|
||||
.nf
|
||||
.B #include <proc/namespace.h>
|
||||
.B #include <procps/misc.h>
|
||||
.PP
|
||||
.BI "int procps_ns_get_id(const char * " name ");"
|
||||
.BI "const char *procps_ns_get_name(const int " id ");"
|
||||
.BI "int procps_ns_read_pid(const int " pid ", struct procps_namespaces * " nsp ");"
|
||||
Platform Particulars
|
||||
.RS 4
|
||||
.PP
|
||||
.B #include <proc/sysinfo.h>
|
||||
.B "long procps_cpu_count (void);"
|
||||
.B "long procps_hertz_get (void);"
|
||||
.B "unsigned int procps_pid_length (void);"
|
||||
.B "int procps_linux_version (void);"
|
||||
.RE
|
||||
.PP
|
||||
.B long procps_cpu_count(void);
|
||||
.B long procps_hertz_get(void);
|
||||
.BI "int procps_loadavg(double * " av1 ", double * " av5 ", double * " av15 ");"
|
||||
.B unsigned int procps_pid_length(void);
|
||||
Runtime Particulars
|
||||
.PP
|
||||
.B #include <proc/uptime.h>
|
||||
.RS 4
|
||||
.BI "int procps_loadavg (double * " av1 ", double * " av5 ", double * " av15 ");"
|
||||
.BI "int procps_uptime (double * " uptime_secs ", double * " idle_secs ");"
|
||||
.B "char * procps_uptime_sprint (void);"
|
||||
.B "char * procps_uptime_sprint_short (void);"
|
||||
.RE
|
||||
.PP
|
||||
.BI "int procps_uptime(double * " uptime_secs ", double * " idle_secs ");"
|
||||
.B char *procps_uptime_sprint(void);
|
||||
.B char *procps_uptime_sprint_short(void);
|
||||
Namespace Particulars
|
||||
.PP
|
||||
.B #include <proc/version.h>
|
||||
.PP
|
||||
.B int procps_linux_version(void);
|
||||
.RS 4
|
||||
.BI "int procps_ns_get_id (const char * " name ");"
|
||||
.BI "const char * procps_ns_get_name (int " id ");"
|
||||
.BI "int procps_ns_read_pid (int " pid ", struct procps_ns * " nsp ");"
|
||||
.RE
|
||||
.sp
|
||||
Link with \fI\-lprocps\fP.
|
||||
.SH DESCRIPTION
|
||||
This manual page describes the miscellaneous API functions of the
|
||||
.B procps
|
||||
library.
|
||||
|
||||
.SH DESCRIPTION
|
||||
.BR procps_cpu_count ()
|
||||
returns the number of CPUs that are currently online. On most systems returns
|
||||
the value of
|
||||
returns the number of CPUs that are currently online as
|
||||
.BI sysconf( _SC_NPROCESSORS_ONLY )
|
||||
or assumed to be \fI1\fR.
|
||||
or an assumed \fI1\fR.
|
||||
|
||||
.BR procps_hertz_get ()
|
||||
returns the number of clock ticks per second. On most systems returns the
|
||||
value of
|
||||
returns the number of clock ticks per second as
|
||||
.BI sysconf( _SC_CLK_TCK )
|
||||
or assumed to be \fI100\fR. Divide certain values returned in the
|
||||
in the \fI/proc\fR filesystem by this value to convert from ticks to seconds.
|
||||
|
||||
.BR procps_loadavg ()
|
||||
Fetches the system load average and puts the 1, 5 and 15 minute averages into
|
||||
the locations in the given pointers. If the relevant pointer is \fINULL\fR then
|
||||
.BR procps_loadavg ()
|
||||
will not set that value.
|
||||
or an assumed \fI100\fR.
|
||||
Dividing tics by this value yields seconds.
|
||||
|
||||
.BR procps_pid_length ()
|
||||
Returns the maximum string length for a PID on the system. For example, if the largest
|
||||
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
|
||||
\fI/proc/sys/kernel/pid_max\fR is unreadable, the value is assumed to be \fI5\fR.
|
||||
|
||||
.BR procps_linux_version ()
|
||||
returns the current Linux version as an integer. On non-Linux systems that
|
||||
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 Linux version consists of a triple of positive integers representing
|
||||
the major, minor and patch versions of the kernel.
|
||||
.PP
|
||||
The library provides 3 macros for separating out the components.
|
||||
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.
|
||||
.RS 4
|
||||
.TP 1.2i
|
||||
.BR LINUX_VERSION_MAJOR (ver)
|
||||
Extract the major component from the given version integer.
|
||||
.TP
|
||||
.BR LINUX_VERSION_MINOR (ver)
|
||||
Extract the minor component from the given version integer.
|
||||
.TP
|
||||
.BR LINUX_VERSION_PATCH (ver)
|
||||
Extract the patch component from the given version integer.
|
||||
.PP
|
||||
LINUX_VERSION(\ major\ ,\ minor\ ,\ patch\ )
|
||||
.PP
|
||||
LINUX_VERSION_MAJOR(\ ver\ )
|
||||
.PP
|
||||
LINUX_VERSION_MINOR(\ ver\ )
|
||||
.PP
|
||||
LINUX_VERSION_PATCH(\ ver\ )
|
||||
.RE
|
||||
.PP
|
||||
To encode a given Linux version, such as using it to compare against the current
|
||||
version, use the following macro:
|
||||
.TP
|
||||
.BI LINUX_VERSION( major , minor , patch )
|
||||
.PP
|
||||
.BR procps_uptime ()
|
||||
returns the uptime and idle time of the system. Either the
|
||||
\fIuptime_secs\fR or \fIidle_secs\fR can be \fBNULL\fR in which case that
|
||||
variable will not be returned.
|
||||
|
||||
The \fBsprint\fR variety of the functions return a human-readable
|
||||
string of the uptime and other statistics.
|
||||
|
||||
.BR procps_ns_get_id ()
|
||||
finds the ID of the namespace for the given namespace name.
|
||||
|
||||
.BR procps_ns_get_name ()
|
||||
finds the name of the namespace of the given integer ID.
|
||||
|
||||
.BR procps_ns_read_pid ()
|
||||
puts the inodes for the namespaces of the given process into
|
||||
the array pointed to \fInsp\fR.
|
||||
|
||||
.SH RETURN VALUE
|
||||
For
|
||||
.BR procps_cpu_count "() , " procps_hertz_get "() and " procps_pid_length ()
|
||||
see the \fBDESCRIPTION\fR section for return values.
|
||||
|
||||
.BR procps_loadavg ()
|
||||
returns 0 on success. On failure, it
|
||||
returns a negative integer to one of the values defined below.
|
||||
.TP
|
||||
.B -ERANGE
|
||||
Unable to parse the loadavg file.
|
||||
.PP
|
||||
fetches the system load average and puts the 1, 5 and 15 minute averages into
|
||||
location(s) specified by any pointer which is not \fINULL\fR.
|
||||
|
||||
.BR procps_linux_version ()
|
||||
returns a positive integer encoding the Linux version if successful. Otherwise
|
||||
returns a negative integer to one of the values defined below.
|
||||
.TP
|
||||
.B -EIO
|
||||
The procps library was unable to read the osrelease file.
|
||||
.TP
|
||||
.B -ERANGE
|
||||
Unable to parse the osrelease file.
|
||||
.BR procps_uptime ()
|
||||
returns uptime and/or idle seconds into location(s) specified by any pointer
|
||||
which is not \fINULL\fR.
|
||||
The \fBsprint\fR varieties return a human-readable string in one of two forms.
|
||||
.RS 4
|
||||
.PP
|
||||
.BR procps_linux_version ()
|
||||
may also return any (negated) value that \fBfopen\fR() may set errno to.
|
||||
HH:MM:SS up HH:MM, # users, load average: 1, 5, 15 MM averages
|
||||
.PP
|
||||
up HH, MM
|
||||
.RE
|
||||
|
||||
.BR procps_ns_get_id ()
|
||||
returns an integer for the namespace ID for the given name or
|
||||
.B \-EINVAL
|
||||
for an invalid input or an unknown namespace name.
|
||||
returns the integer id (enum namespace_type) of the namespace for the given namespace \fIname\fR.
|
||||
|
||||
.BR procps_ns_get_name ()
|
||||
returns a statically allocated string containing the name of the
|
||||
namespace for the given ID. If the name is not found the function
|
||||
returns
|
||||
.B NULL
|
||||
returns the name of the namespace for the given \fIid\fR (enum namespace_type).
|
||||
|
||||
.BR procps_ns_read_pid ()
|
||||
Returns 0 on success and \fB\-EINVAL\fR on failure.
|
||||
|
||||
.BR procps_uptime ()
|
||||
returns 0 on success. On failure, it
|
||||
returns a negative integer to one of the values defined below.
|
||||
.TP
|
||||
.B -ERANGE
|
||||
Unable to parse the uptime file.
|
||||
returns the inodes for the namespaces of the given process in the
|
||||
procps_ns structure pointed to by \fInsp\fR.
|
||||
Those inodes will appear in the order proscribed by enum namespace_type.
|
||||
.PP
|
||||
.BR procps_uptime ()
|
||||
may also return any (negated) value that \fBfopen\fR() may set errno to.
|
||||
.RS 4
|
||||
.nf
|
||||
enum namespace_type {
|
||||
PROCPS_NS_IPC,
|
||||
PROCPS_NS_MNT,
|
||||
PROCPS_NS_NET,
|
||||
PROCPS_NS_PID,
|
||||
PROCPS_NS_USER,
|
||||
PROCPS_NS_UTS
|
||||
};
|
||||
.fi
|
||||
.RE
|
||||
|
||||
.BR procps_uptime_sprint_short ()
|
||||
return a string from a statically allocated buffer which displays uptime.
|
||||
|
||||
.BR procps_uptime_sprint ()
|
||||
also displays users and load average in the buffer. The formats are the
|
||||
same as
|
||||
.BR uptime (1)
|
||||
with and without the
|
||||
.B \-p
|
||||
option.
|
||||
.SH RETURN VALUE
|
||||
.SS 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.
|
||||
|
||||
.SS Functions Returning an `address'
|
||||
An error will be indicated by a NULL return pointer
|
||||
with the reason found in the formal errno value.
|
||||
|
||||
.SH FILES
|
||||
.TP
|
||||
@ -194,20 +154,10 @@ Contains the value at which PIDs wrap around, one greater than the maximum PID v
|
||||
.I /proc/uptime
|
||||
The raw values for uptime and idle time.
|
||||
.TP
|
||||
.IB /proc/ PID /ns
|
||||
.IB /proc/<PID>/ns
|
||||
contains the set of namespaces for a particular \fBPID\fR.
|
||||
|
||||
.SH BUGS
|
||||
Due to the way the three numbers are encoded into a single integer,
|
||||
.BR procps_linux_version ()
|
||||
and the associated macros assume 255 for the maximum value for the
|
||||
minor and patch level and 32767 (hex 0x7fff) for the maximum value
|
||||
for the major version. In other words, when Linux v 32768.0.0 comes
|
||||
out, this function will break.
|
||||
.\" Maj/6yr - In 7452 we'll think of something
|
||||
|
||||
.SH SEE ALSO
|
||||
.BR uptime (1),
|
||||
.BR fopen (3),
|
||||
.BR sysconf (3),
|
||||
.BR procps (3).
|
||||
.BR procps_pids (3).
|
||||
.BR proc (5).
|
||||
|
Loading…
Reference in New Issue
Block a user