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KVM_GETPROCS(3) 	     Library Functions Manual		 KVM_GETPROCS(3)

NAME
     kvm_getprocs, kvm_getargv, kvm_getenvv -- access user process state

LIBRARY
     Kernel Data Access Library (libkvm, -lkvm)

SYNOPSIS
     #include <kvm.h>
     #include <sys/param.h>
     #include <sys/sysctl.h>
     #include <sys/user.h>

     struct kinfo_proc *
     kvm_getprocs(kvm_t *kd, int op, int arg, int *cnt);

     char **
     kvm_getargv(kvm_t *kd, const struct kinfo_proc *p, int nchr);

     char **
     kvm_getenvv(kvm_t *kd, const struct kinfo_proc *p, int nchr);

DESCRIPTION
     The  kvm_getprocs() function returns a (sub-)set of active processes in the
     kernel indicated by kd.  The op and arg arguments	constitute  a  predicate
     which  limits the set of processes returned.  The value of op describes the
     filtering predicate as follows:

	   KERN_PROC_ALL	 all processes and kernel visible threads
	   KERN_PROC_PROC	 all processes, without threads
	   KERN_PROC_PID	 processes with process ID arg
	   KERN_PROC_PGRP	 processes with process group arg
	   KERN_PROC_SESSION	 processes with session arg
	   KERN_PROC_TTY	 processes with TTY arg
	   KERN_PROC_UID	 processes with effective user ID arg
	   KERN_PROC_RUID	 processes with real user ID arg
	   KERN_PROC_INC_THREAD  modifier to return all kernel	visible  threads
				 when  filtering  by  process ID, process group,
				 TTY, user ID, and real user ID

     The number of processes found is returned in the reference  parameter  cnt.
     The  processes are returned as a contiguous array of kinfo_proc structures.
     This memory is locally allocated, and subsequent  calls  to  kvm_getprocs()
     and kvm_close() will overwrite this storage.

     The  kvm_getargv()  function returns a null-terminated argument vector that
     corresponds to the command line arguments passed to process indicated by p.
     Most likely, these arguments correspond to the values passed to exec(3)  on
     process creation.	This information is, however, deliberately under control
     of  the  process itself.  Note that the original command name can be found,
     unaltered, in the	p_comm	field  of  the	process  structure  returned  by
     kvm_getprocs().

     The  nchr	argument  indicates  the maximum number of characters, including
     null bytes, to use in building the strings.  If this  amount  is  exceeded,
     the  string causing the overflow is truncated and the partial result is re-
     turned.  This is handy for programs like ps(1) and w(1) that print  only  a
     one line summary of a command and should not copy out large amounts of text
     only  to  ignore it.  If nchr is zero, no limit is imposed and all argument
     strings are returned in their entirety.

     The memory allocated to the argv pointers and string storage  is  owned  by
     the  kvm  library.   Subsequent  kvm_getprocs() and kvm_close(3) calls will
     clobber this storage.

     The kvm_getenvv() function is similar to kvm_getargv() but returns the vec-
     tor of environment strings.  This data is also alterable by the process.

RETURN VALUES
     The kvm_getprocs(), kvm_getargv(), and kvm_getenvv() functions return  NULL
     on failure.

SEE ALSO
     kvm(3),  kvm_close(3),  kvm_geterr(3), kvm_nlist(3), kvm_open(3), kvm_open-
     files(3), kvm_read(3), kvm_write(3)

BUGS
     These routines do not belong in the kvm interface.

FreeBSD ports 15.1		November 22, 2011		 KVM_GETPROCS(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=kvm_getenvv&manpath=FreeBSD+15.1-RELEASE+and+Ports>

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