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ELF_ERRMSG(3) FreeBSD Library Functions Manual ELF_ERRMSG(3)
NAME
elf_errmsg, elf_errno - ELF library error message handling
LIBRARY
ELF Access Library (libelf, -lelf)
SYNOPSIS
#include <libelf.h>
int
elf_errno(void);
const char *
elf_errmsg(int error);
DESCRIPTION
When an error occurs during an ELF library API call, the library encodes
the error using an error number and stores the error number internally
for retrieval by the application at a later point of time. Error numbers
may contain an OS supplied error code in addition to an ELF API specific
error code. An error number value of zero indicates no error.
Function elf_errno() is used to retrieve the last error recorded by the
ELF library. Invoking this function has the side-effect of resetting the
ELF library's recorded error number to zero.
The function elf_errmsg() returns a null-terminated string with a human
readable description of the error specified in argument error. A zero
value for argument error retrieves the most recent error encountered by
the ELF library. An argument value of -1 behaves identically, except
that it guarantees a non-NULL return from elf_errmsg().
RETURN VALUES
Function elf_errno() returns a non-zero value encoding the last error
encountered by the ELF library, or zero if no error was encountered.
Function elf_errmsg() returns a pointer to library local storage for non-
zero values of argument error. With a zero argument, the function will
return a NULL pointer if no error had been encountered by the library, or
will return a pointer to library local storage containing an appropriate
message otherwise.
EXAMPLES
Clearing the ELF library's recorded error number can be accomplished by
invoking elf_errno() and discarding its return value.
/* clear error */
(void) elf_errno();
Retrieving a human-readable description of the current error number can
be done with the following snippet:
int err;
const char *errmsg;
...
err = elf_errno();
if (err != 0)
FreeBSD 14.0-RELEASE-p11 June 11, 2006 FreeBSD 14.0-RELEASE-p11