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unw_step(3) [debian man page]

UNW_STEP(3)						       Programming Library						       UNW_STEP(3)

NAME
unw_step -- advance to next stack frame SYNOPSIS
#include <libunwind.h> int unw_step(unw_cursor_t *cp); DESCRIPTION
The unw_step() routine advances the unwind cursor cp to the next older, less deeply nested stack frame. RETURN VALUE
On successful completion, unw_step() returns a positive value if the updated cursor refers to a valid stack frame, or 0 if the previous stack frame was the last frame in the chain. On error, the negative value of one of the error-codes below is returned. THREAD AND SIGNAL SAFETY
unw_step() is thread-safe. If cursor cp is in the local address-space, this routine is also safe to use from a signal handler. ERRORS
UNW_EUNSPEC An unspecified error occurred. UNW_ENOINFO Libunwind was unable to locate the unwind-info needed to complete the operation. UNW_EBADVERSION The unwind-info needed to complete the operation has a version or a format that is not understood by libunwind. UNW_EINVALIDIP The instruction-pointer (``program-counter'') of the next stack frame is invalid (e.g., not properly aligned). UNW_EBADFRAME The next stack frame is invalid. UNW_ESTOPUNWIND Returned if a call to find_proc_info() returned -UNW_ESTOPUNWIND. In addition, unw_step() may return any error returned by the find_proc_info(), get_dyn_info_list_addr(), access_mem(), access_reg(), or access_fpreg() call-backs (see unw_create_addr_space(3)). SEE ALSO
libunwind(3), unw_create_addr_space(3) AUTHOR
David Mosberger-Tang Email: dmosberger@gmail.com WWW: http://www.nongnu.org/libunwind/. Programming Library 16 August 2007 UNW_STEP(3)

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UNW_SET_FPREG(3)					       Programming Library						  UNW_SET_FPREG(3)

NAME
unw_set_fpreg -- set contents of floating-point register SYNOPSIS
#include <libunwind.h> int unw_set_fpreg(unw_cursor_t *cp, unw_regnum_t reg, unw_fpreg_t val); DESCRIPTION
The unw_set_fpreg() 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_fpreg() can only write the contents of floating-point registers. See unw_set_reg(3) for a way to write registers which fit in a single word. RETURN VALUE
On successful completion, unw_set_fpreg() returns 0. Otherwise the negative value of one of the error-codes below is returned. THREAD AND SIGNAL SAFETY
unw_set_fpreg() 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_fpreg() 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_fpreg(3), unw_is_fpreg(3), unw_is_signal_frame(3), unw_set_reg(3) AUTHOR
David Mosberger-Tang Email: dmosberger@gmail.com WWW: http://www.nongnu.org/libunwind/. Programming Library 16 August 2007 UNW_SET_FPREG(3)
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