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KVM_GETPROCS(3)		 BSD Library Functions Manual	       KVM_GETPROCS(3)

     kvm_getprocs, kvm_getargv,	kvm_getenvv -- access user process state

     Kernel Data Access	Library	(libkvm, -lkvm)

     #include <kvm.h>
     #include <sys/param.h>
     #include <sys/sysctl.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);

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

	   KERN_PROC_ALL	 all processes
	   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

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

     kvm_getargv() 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 con-
     trol 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
     returned.	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 ar-
     gument 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
     vector of environment strings.  This data is also alterable by the

     kvm_getprocs(), kvm_getargv(), and	kvm_getenvv(), all return NULL on

     These routines do not belong in the kvm interface.

     kvm(3), kvm_close(3), kvm_geterr(3), kvm_nlist(3),	kvm_open(3),
     kvm_openfiles(3), kvm_read(3), kvm_write(3)

BSD				 June 4, 1993				   BSD


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