1.\" Copyright (c) 1992, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software developed by the Computer Systems 5.\" Engineering group at Lawrence Berkeley Laboratory under DARPA contract 6.\" BG 91-66 and contributed to Berkeley. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed by the University of 19.\" California, Berkeley and its contributors. 20.\" 4. Neither the name of the University nor the names of its contributors 21.\" may be used to endorse or promote products derived from this software 22.\" without specific prior written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34.\" SUCH DAMAGE. 35.\" 36.\" @(#)kvm_getprocs.3 8.1 (Berkeley) 6/4/93 37.\" $FreeBSD$ 38.\" 39.Dd June 4, 1993 40.Dt KVM_GETPROCS 3 41.Os 42.Sh NAME 43.Nm kvm_getprocs , 44.Nm kvm_getargv , 45.Nm kvm_getenvv 46.Nd access user process state 47.Sh LIBRARY 48.Lb libkvm 49.Sh SYNOPSIS 50.In kvm.h 51.In sys/param.h 52.In sys/sysctl.h 53.In sys/user.h 54.\" .Fa kvm_t *kd 55.Ft struct kinfo_proc * 56.Fn kvm_getprocs "kvm_t *kd" "int op" "int arg" "int *cnt" 57.Ft char ** 58.Fn kvm_getargv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 59.Ft char ** 60.Fn kvm_getenvv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 61.Sh DESCRIPTION 62The 63.Fn kvm_getprocs 64function returns a (sub-)set of active processes in the kernel indicated by 65.Fa kd . 66The 67.Fa op 68and 69.Fa arg 70arguments constitute a predicate which limits the set of processes 71returned. The value of 72.Fa op 73describes the filtering predicate as follows: 74.Pp 75.Bl -tag -width 20n -offset indent -compact 76.It Sy KERN_PROC_ALL 77all processes 78.It Sy KERN_PROC_PID 79processes with process id 80.Fa arg 81.It Sy KERN_PROC_PGRP 82processes with process group 83.Fa arg 84.It Sy KERN_PROC_SESSION 85processes with session 86.Fa arg 87.It Sy KERN_PROC_TTY 88processes with tty 89.Fa arg 90.It Sy KERN_PROC_UID 91processes with effective user id 92.Fa arg 93.It Sy KERN_PROC_RUID 94processes with real user id 95.Fa arg 96.El 97.Pp 98The number of processes found is returned in the reference parameter 99.Fa cnt . 100The processes are returned as a contiguous array of kinfo_proc structures. 101This memory is locally allocated, and subsequent calls to 102.Fn kvm_getprocs 103and 104.Fn kvm_close 105will overwrite this storage. 106.Pp 107The 108.Fn kvm_getargv 109function returns a null-terminated argument vector that corresponds to the 110command line arguments passed to process indicated by 111.Fa p . 112Most likely, these arguments correspond to the values passed to 113.Xr exec 3 114on process creation. This information is, however, 115deliberately under control of the process itself. 116Note that the original command name can be found, unaltered, 117in the p_comm field of the process structure returned by 118.Fn kvm_getprocs . 119.Pp 120The 121.Fa nchr 122argument indicates the maximum number of characters, including null bytes, 123to use in building the strings. If this amount is exceeded, the string 124causing the overflow is truncated and the partial result is returned. 125This is handy for programs like 126.Xr ps 1 127and 128.Xr w 1 129that print only a one line summary of a command and should not copy 130out large amounts of text only to ignore it. 131If 132.Fa nchr 133is zero, no limit is imposed and all argument strings are returned in 134their entirety. 135.Pp 136The memory allocated to the argv pointers and string storage 137is owned by the kvm library. Subsequent 138.Fn kvm_getprocs 139and 140.Xr kvm_close 3 141calls will clobber this storage. 142.Pp 143The 144.Fn kvm_getenvv 145function is similar to 146.Fn kvm_getargv 147but returns the vector of environment strings. This data is 148also alterable by the process. 149.Sh RETURN VALUES 150The 151.Fn kvm_getprocs , 152.Fn kvm_getargv , 153and 154.Fn kvm_getenvv 155functions return 156.Dv NULL 157on failure. 158.Sh BUGS 159These routines do not belong in the kvm interface. 160.Sh SEE ALSO 161.Xr kvm 3 , 162.Xr kvm_close 3 , 163.Xr kvm_geterr 3 , 164.Xr kvm_nlist 3 , 165.Xr kvm_open 3 , 166.Xr kvm_openfiles 3 , 167.Xr kvm_read 3 , 168.Xr kvm_write 3 169