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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_GET_PROC_NAME(3)					       Programming Library					      UNW_GET_PROC_NAME(3)

NAME
unw_get_proc_name -- get name of current procedure SYNOPSIS
#include <libunwind.h> int unw_get_proc_name(unw_cursor_t *cp, char *bufp, size_t len, unw_word_t *offp); DESCRIPTION
The unw_get_proc_name() routine returns the name of the procedure that created the stack frame identified by argument cp. The bufp argu- ment is a pointer to a character buffer that is at least len bytes long. This buffer is used to return the name of the procedure. The offp argument is a pointer to a word that is used to return the byte-offset of the instruction-pointer saved in the stack frame identified by cp, relative to the start of the procedure. For example, if procedure foo() starts at address 0x40003000, then invoking unw_get_proc_name() on a stack frame with an instruction-pointer value of 0x40003080 would return a value of 0x80 in the word pointed to by offp (assuming the procedure is at least 0x80 bytes long). Note that on some platforms there is no reliable way to distinguish between procedure names and ordinary labels. Furthermore, if symbol information has been stripped from a program, procedure names may be completely unavailable or may be limited to those exported via a dynamic symbol table. In such cases, unw_get_proc_name() may return the name of a label or a preceeding (nearby) procedure. However, the offset returned through offp is always relative to the returned name, which ensures that the value (address) of the returned name plus the returned offset will always be equal to the instruction-pointer of the stack frame identified by cp. RETURN VALUE
On successful completion, unw_get_proc_name() returns 0. Otherwise the negative value of one of the error-codes below is returned. THREAD AND SIGNAL SAFETY
unw_get_proc_name() 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 determine the name of the procedure. UNW_ENOMME The procedure name is too long to fit in the buffer provided. A truncated version of the name has been returned. In addition, unw_get_proc_name() may return any error returned by the access_mem() call-back (see unw_create_addr_space(3)). SEE ALSO
libunwind(3), unw_get_proc_info(3) AUTHOR
David Mosberger-Tang Email: dmosberger@gmail.com WWW: http://www.nongnu.org/libunwind/. Programming Library 16 August 2007 UNW_GET_PROC_NAME(3)
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