diff options
Diffstat (limited to 'newlib/libc/string/strerror.c')
| -rw-r--r-- | newlib/libc/string/strerror.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/newlib/libc/string/strerror.c b/newlib/libc/string/strerror.c index 043763141..61e40ab7a 100644 --- a/newlib/libc/string/strerror.c +++ b/newlib/libc/string/strerror.c @@ -301,6 +301,17 @@ declares that subsequent calls to <<strerror>> may overwrite the result string; therefore portable code cannot depend on the reentrancy of this subroutine. +Although this implementation of <<strerror>> guarantees a non-null +result with a NUL-terminator, some implementations return <<NULL>> +on failure. Although POSIX allows <<strerror>> to set <<errno>> +to EINVAL on failure, this implementation does not do so (unless +you provide <<_user_strerror>>). + +POSIX recommends that unknown <[errnum]> result in a message +including that value, however it is not a requirement and this +implementation does not provide that information (unless you +provide <<_user_strerror>>). + This implementation of <<strerror>> provides for user-defined extensibility. <<errno.h>> defines <[__ELASTERROR]>, which can be used as a base for user-defined error values. If the user supplies a @@ -313,6 +324,9 @@ character pointer. If <[errnum]> is unknown to <<_user_strerror>>, <<_user_strerror>> returns <[NULL]>. The default <<_user_strerror>> returns <[NULL]> for all input values. +Note that <<_user_sterror>> must be thread-safe and not alter <<errno>> +if <<strerror_r>> is to comply with POSIX. + <<strerror>> requires no supporting OS subroutines. QUICKREF |