Patchkit 5 Patchkit 5
chatr - change program's internal attributes
chatr [+ed flag] file...
Change the program attribute that enables user code to execute from
data (stack or heap). The flag values are enable and disable to change
The chatr command changes a program's internal attributes. Upon comple-
tion, chatr prints the file's old and new values to standard output.
The +ed option of chatr is used to specify that a particular binary must be
able to execute from its stack or heap, regardless of the system default
setting. This allows a restrictive system default while not preventing leg-
itimate programs from executing code in data. Ideally this option should be
set (if needed) by the program's provider, to minimize the need for manual
intervention by system administrators.
The chatr command can only be used to modify the attributes of executable
object files, and shared libraries. It does not support archived libraries,
or object files that have been relocated.
The following environment variables affect the execution of the chatr com-
Provides a default value for the internationalization variables that
are unset or null. If LANG is unset or null, the corresponding value
from the default locale is used. If any of the internationalization
variables contain an invalid setting, the utility behaves as if none of
the variables had been defined.
If set to a non-empty string value, overrides the values of all the
other internationalization variables.
Determines the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to multi-
byte characters in arguments).
Determines the locale for the format and contents of diagnostic mes-
sages written to standard error.
Determines the location of message catalogues for the processing of