elf_errno(3) - NetBSD Manual Pages

ELF_ERRMSG(3)           NetBSD Library Functions Manual          ELF_ERRMSG(3)


NAME

     elf_errmsg, elf_errno -- ELF library error message handling


LIBRARY

     ELF Object Manipulation 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)
                   errmsg = elf_errmsg(err);


SEE ALSO

     elf(3), gelf(3)


BUGS

     Function elf_errmsg() is not localized.

NetBSD 10.99                     June 11, 2006                    NetBSD 10.99