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.\" .Fa kvm_t *kd 54.Ft struct kinfo_proc * 55.Fn kvm_getprocs "kvm_t *kd" "int op" "int arg" "int *cnt" 56.Ft char ** 57.Fn kvm_getargv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 58.Ft char ** 59.Fn kvm_getenvv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 60.Sh DESCRIPTION 61.Fn kvm_getprocs 62returns a (sub-)set of active processes in the kernel indicated by 63.Fa kd . 64The 65.Fa op 66and 67.Fa arg 68arguments constitute a predicate which limits the set of processes 69returned. The value of 70.Fa op 71describes the filtering predicate as follows: 72.Pp 73.Bl -tag -width 20n -offset indent -compact 74.It Sy KERN_PROC_ALL 75all processes 76.It Sy KERN_PROC_PID 77processes with process id 78.Fa arg 79.It Sy KERN_PROC_PGRP 80processes with process group 81.Fa arg 82.It Sy KERN_PROC_SESSION 83processes with session 84.Fa arg 85.It Sy KERN_PROC_TTY 86processes with tty 87.Fa arg 88.It Sy KERN_PROC_UID 89processes with effective user id 90.Fa arg 91.It Sy KERN_PROC_RUID 92processes with real user id 93.Fa arg 94.El 95.Pp 96The number of processes found is returned in the reference parameter 97.Fa cnt . 98The processes are returned as a contiguous array of kinfo_proc structures. 99This memory is locally allocated, and subsequent calls to 100.Fn kvm_getprocs 101and 102.Fn kvm_close 103will overwrite this storage. 104.Pp 105.Fn kvm_getargv 106returns a null-terminated argument vector that corresponds to the 107command line arguments passed to process indicated by 108.Fa p . 109Most likely, these arguments correspond to the values passed to 110.Xr exec 3 111on process creation. This information is, however, 112deliberately under control of the process itself. 113Note that the original command name can be found, unaltered, 114in the p_comm field of the process structure returned by 115.Fn kvm_getprocs . 116.Pp 117The 118.Fa nchr 119argument indicates the maximum number of characters, including null bytes, 120to use in building the strings. If this amount is exceeded, the string 121causing the overflow is truncated and the partial result is returned. 122This is handy for programs like 123.Xr ps 1 124and 125.Xr w 1 126that print only a one line summary of a command and should not copy 127out large amounts of text only to ignore it. 128If 129.Fa nchr 130is zero, no limit is imposed and all argument strings are returned in 131their entirety. 132.Pp 133The memory allocated to the argv pointers and string storage 134is owned by the kvm library. Subsequent 135.Fn kvm_getprocs 136and 137.Xr kvm_close 3 138calls will clobber this storage. 139.Pp 140The 141.Fn kvm_getenvv 142function is similar to 143.Fn kvm_getargv 144but returns the vector of environment strings. This data is 145also alterable by the process. 146.Sh RETURN VALUES 147.Fn kvm_getprocs , 148.Fn kvm_getargv , 149and 150.Fn kvm_getenvv , 151all return 152.Dv NULL 153on failure. 154.Sh BUGS 155These routines do not belong in the kvm interface. 156.Sh SEE ALSO 157.Xr kvm 3 , 158.Xr kvm_close 3 , 159.Xr kvm_geterr 3 , 160.Xr kvm_nlist 3 , 161.Xr kvm_open 3 , 162.Xr kvm_openfiles 3 , 163.Xr kvm_read 3 , 164.Xr kvm_write 3 165