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: src/lib/libkvm/kvm_getprocs.3,v 1.6.2.7 2003/04/29 14:37:04 trhodes Exp $ 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 62.Fn kvm_getprocs 63returns a (sub-)set of active processes in the kernel indicated by 64.Fa kd . 65The 66.Fa op 67and 68.Fa arg 69arguments constitute a predicate which limits the set of processes 70returned. The value of 71.Fa op 72describes the filtering predicate as follows: 73.Pp 74.Bl -tag -width 20n -offset indent -compact 75.It Sy KERN_PROC_ALL 76all processes 77.It Sy KERN_PROC_PID 78processes with process id 79.Fa arg 80.It Sy KERN_PROC_PGRP 81processes with process group 82.Fa arg 83.It Sy KERN_PROC_SESSION 84processes with session 85.Fa arg 86.It Sy KERN_PROC_TTY 87processes with tty 88.Fa arg 89.It Sy KERN_PROC_UID 90processes with effective user id 91.Fa arg 92.It Sy KERN_PROC_RUID 93processes with real user id 94.Fa arg 95.El 96.Pp 97The number of processes found is returned in the reference parameter 98.Fa cnt . 99The processes are returned as a contiguous array of kinfo_proc structures. 100This memory is locally allocated, and subsequent calls to 101.Fn kvm_getprocs 102and 103.Fn kvm_close 104will overwrite this storage. 105.Pp 106.Fn kvm_getargv 107returns a null-terminated argument vector that corresponds to the 108command line arguments passed to process indicated by 109.Fa p . 110Most likely, these arguments correspond to the values passed to 111.Xr exec 3 112on process creation. This information is, however, 113deliberately under control of the process itself. 114Note that the original command name can be found, unaltered, 115in the p_comm field of the process structure returned by 116.Fn kvm_getprocs . 117.Pp 118The 119.Fa nchr 120argument indicates the maximum number of characters, including null bytes, 121to use in building the strings. If this amount is exceeded, the string 122causing the overflow is truncated and the partial result is returned. 123This is handy for programs like 124.Xr ps 1 125and 126.Xr w 1 127that print only a one line summary of a command and should not copy 128out large amounts of text only to ignore it. 129If 130.Fa nchr 131is zero, no limit is imposed and all argument strings are returned in 132their entirety. 133.Pp 134The memory allocated to the argv pointers and string storage 135is owned by the kvm library. Subsequent 136.Fn kvm_getprocs 137and 138.Xr kvm_close 3 139calls will clobber this storage. 140.Pp 141The 142.Fn kvm_getenvv 143function is similar to 144.Fn kvm_getargv 145but returns the vector of environment strings. This data is 146also alterable by the process. 147.Sh RETURN VALUES 148.Fn kvm_getprocs , 149.Fn kvm_getargv , 150and 151.Fn kvm_getenvv , 152all return 153.Dv NULL 154on failure. 155.Sh BUGS 156These routines do not belong in the kvm interface. 157.Sh SEE ALSO 158.Xr kvm 3 , 159.Xr kvm_close 3 , 160.Xr kvm_geterr 3 , 161.Xr kvm_nlist 3 , 162.Xr kvm_open 3 , 163.Xr kvm_openfiles 3 , 164.Xr kvm_read 3 , 165.Xr kvm_write 3 166