xref: /freebsd/usr.bin/elfctl/elfctl.1 (revision ce6a89e27cd190313be39bb479880aeda4778436)
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3.\" This software was developed by Bora Ozarslan under sponsorship from
4.\" the FreeBSD Foundation.
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27.\" $FreeBSD$
28.\"
29.Dd March 1, 2020
30.Dt ELFCTL 1
31.Os
32.Sh NAME
33.Nm elfctl
34.Nd change an ELF binary's feature control note
35.Sh SYNOPSIS
36.Nm
37.Op Fl h | Fl -help
38.Op Fl l
39.Op Fl e Ar featurelist
40.Ar
41.Sh DESCRIPTION
42The
43.Nm
44utility modifies feature flags in the feature control note in an ELF binary.
45.Pp
46The options are as follows:
47.Bl -tag -width indent
48.It Fl h | Fl -help
49Print a usage message and exit.
50.It Fl l
51List known ELF feature flags.
52.It Fl e Ar featurelist
53Edit features from the given comma separated list
54.Ar featurelist .
55.Ar featurelist
56starts with one of the three operations:
57.Dq Li +
58to turn on the features,
59.Dq Li -
60to turn off the features,
61.Dq Li =
62to only turn on the given features.
63A comma separated list of feature names follows the operation.
64.El
65.Pp
66If
67.Fl e
68is not specified
69.Nm
70displays the status of each feature in the ELF note in each
71.Ar .
72.Sh EXIT STATUS
73Exit status is 0 on success, and 1 if the command
74fails if a file does not exist, is too short,
75or fails to find or edit features note.
76.Sh EXAMPLES
77The following is an example of a typical usage
78of the
79.Nm
80command:
81.Bd -literal -offset indent
82elfctl file
83elfctl -e +aslr file
84.Ed
85.Sh HISTORY
86.Nm
87first appeared in
88.Fx 13.0 .
89.Sh AUTHORS
90.Nm
91was written by
92.An Bora Ozarslan Mt borako.ozarslan@gmail.com
93under sponsorship from the
94.Fx Foundation.
95