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unw_set_reg(3) [debian man page]

UNW_SET_REG(3)						       Programming Library						    UNW_SET_REG(3)

NAME
unw_set_reg -- set register contents SYNOPSIS
#include <libunwind.h> int unw_set_reg(unw_cursor_t *cp, unw_regnum_t reg, unw_word_t val); DESCRIPTION
The unw_set_reg() routine sets the value of register reg in the stack frame identified by cursor cp to the value passed in val. The register numbering is target-dependent and described in separate manual pages (e.g., libunwind-ia64(3) for the IA-64 target). Further- more, the exact set of accessible registers may depend on the type of frame that cp is referring to. For ordinary stack frames, it is nor- mally possible to access only the preserved (``callee-saved'') registers and frame-related registers (such as the stack-pointer). However, for signal frames (see unw_is_signal_frame(3)), it is usually possible to access all registers. Note that unw_set_reg() can only write the contents of registers whose values fit in a single word. See unw_set_fpreg(3) for a way to write registers which do not fit this constraint. RETURN VALUE
On successful completion, unw_set_reg() returns 0. Otherwise the negative value of one of the error-codes below is returned. THREAD AND SIGNAL SAFETY
unw_set_reg() is thread-safe as well as safe to use from a signal handler. ERRORS
UNW_EUNSPEC An unspecified error occurred. UNW_EBADREG An attempt was made to write a register that is either invalid or not accessible in the current frame. UNW_EREADONLY An attempt was made to write to a read-only register. In addition, unw_set_reg() may return any error returned by the access_mem(), access_reg(), and access_fpreg() call-backs (see unw_cre- ate_addr_space(3)). SEE ALSO
libunwind(3), libunwind-ia64(3), unw_get_reg(3), unw_is_signal_frame(3), unw_set_fpreg(3) AUTHOR
David Mosberger-Tang Email: dmosberger@gmail.com WWW: http://www.nongnu.org/libunwind/. Programming Library 16 August 2007 UNW_SET_REG(3)

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UNW_INIT_REMOTE(3)					       Programming Library						UNW_INIT_REMOTE(3)

NAME
unw_init_remote -- initialize cursor for remote unwinding SYNOPSIS
#include <libunwind.h> int unw_init_remote(unw_cursor_t *c, unw_addr_space_t as, void *arg); DESCRIPTION
The unw_init_remote() routine initializes the unwind cursor pointed to by c for unwinding in the address space identified by as. The as argument can either be set to unw_local_addr_space (local address space) or to an arbitrary address space created with unw_cre- ate_addr_space(). The arg void-pointer tells the address space exactly what entity should be unwound. For example, if unw_local_addr_space is passed in as, then arg needs to be a pointer to a context structure containing the machine-state of the initial stack frame. However, other address-spa- ces may instead expect a process-id, a thread-id, or a pointer to an arbitrary structure which identifies the stack-frame chain to be unwound. In other words, the interpretation of arg is entirely dependent on the address-space in use; libunwind never interprets the argu- ment in any way on its own. Note that unw_init_remote() can be used to initiate unwinding in any process, including the local process in which the unwinder itself is running. However, for local unwinding, it is generally preferable to use unw_init_local() instead, because it is easier to use and because it may perform better. RETURN VALUE
On successful completion, unw_init_remote() returns 0. Otherwise the negative value of one of the error-codes below is returned. THREAD AND SIGNAL SAFETY
unw_init_remote() is thread-safe. If the local address-space is passed in argument as, this routine is also safe to use from a signal han- dler. ERRORS
UNW_EINVAL unw_init_remote() was called in a version of libunwind which supports local unwinding only (this normally happens when defining UNW_LOCAL_ONLY before including <libunwind.h> and then calling unw_init_remote()). UNW_EUNSPEC An unspecified error occurred. UNW_EBADREG A register needed by unw_init_remote() wasn't accessible. SEE ALSO
libunwind(3), unw_create_addr_space(3), unw_init_local(3) AUTHOR
David Mosberger-Tang Email: dmosberger@gmail.com WWW: http://www.nongnu.org/libunwind/. Programming Library 16 August 2007 UNW_INIT_REMOTE(3)

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