Query: patch_active_text
OS: hpux
Section: 5
Format: Original Unix Latex Style Formatted with HTML and a Horizontal Scroll Bar
patch_active_text(5) File Formats Manual patch_active_text(5)NAMEpatch_active_text - dynamically enable or disable running executable text to be modified via mprotect()VALUESFail Safe Default semantics is enabled Allowed values orDESCRIPTIONThis tunable allows write access to text of a running process such that the active text can be modified. When this tunable is enabled, can be used with a special flag, to modify the text of a running executable. By default, does not work on text of a process. Enabling the tunable allows to work on text segments of a process. Making text writable will create a private copy of the text to the process using this feature. Once with special flag allows running text to be modified, further invocations of on text of a process with other prot flags are also allowed. For must always be used with (see mprotect(2)). must always be used on text address range. After the first invocation of further mprotect(2) calls will work on text segments of process with any other prot flags; in other words, will work on text with or any combinations of the above. The only requirement is that both these flags must be invoked first. Who Is Expected to Change This Tunable? System administrators who wish to change the default behavior. Restrictions on Changing Changes to this tunable take effect immediately. When Should the Tunable Be Turned Off? If an application expects to fail on text segments, the tunable should be turned off. What Are the Side Effects of Turning the Tunable Off? Applications will no longer be able to use on text of a process. When Should the Tunable Be Turned On? If an application wants its text segment to be writable and also wants to be able to work on text of processes, this tunable must be turned on. Making text writable will create a private copy of the text to the process using this feature. What Are the Side Effects of Turning the Tunable On? Memory consumption in the system will increase. This is because with the process will create a private copy of the shared text on first invocation. It should also be noted that large page benefits on text segments will be lost. What Other Tunables Should Be Changed at the Same Time? None.WARNINGSAll HP-UX kernel tunable parameters are release specific. This parameter may be removed or have its meaning changed in future releases of HP-UX. Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parameter values. After installation, some tunable parameters may no longer be at the default or recommended values. For information about the effects of installation on tun- able values, consult the documentation for the kernel software being installed. For information about optional kernel software that was factory installed on your system, see atAUTHORwas developed by HP.SEE ALSOmprotect(2), copy_on_write(5) Tunable Kernel Parameters patch_active_text(5)