In Files

  • error.c




Public Class Methods

system_call_error === other => true or false click to toggle source

Return true if the receiver is a generic SystemCallError, or if the error numbers self and other are the same.

               static VALUE
syserr_eqq(self, exc)
    VALUE self, exc;
    VALUE num, e;

    if (!rb_obj_is_kind_of(exc, rb_eSystemCallError)) return Qfalse;
    if (self == rb_eSystemCallError) return Qtrue;

    num = rb_attr_get(exc, rb_intern("errno"));
    if (NIL_P(num)) {
        VALUE klass = CLASS_OF(exc);

        while (TYPE(klass) == T_ICLASS || FL_TEST(klass, FL_SINGLETON)) {
            klass = (VALUE)RCLASS(klass)->super;
        num = rb_const_get(klass, rb_intern("Errno"));
    e = rb_const_get(self, rb_intern("Errno"));
    if (FIXNUM_P(num) ? num == e : rb_equal(num, e))
        return Qtrue;
    return Qfalse;
new(msg, errno) => system_call_error_subclass click to toggle source

If errno corresponds to a known system error code, constructs the appropriate Errno class for that error, otherwise constructs a generic SystemCallError object. The error number is subsequently available via the errno method.

               static VALUE
syserr_initialize(argc, argv, self)
    int argc;
    VALUE *argv;
    VALUE self;
#if !defined(_WIN32) && !defined(__VMS)
    char *strerror();
    char *err;
    VALUE mesg, error;
    VALUE klass = rb_obj_class(self);

    if (klass == rb_eSystemCallError) {
        rb_scan_args(argc, argv, "11", &mesg, &error);
        if (argc == 1 && FIXNUM_P(mesg)) {
            error = mesg; mesg = Qnil;
        if (!NIL_P(error) && st_lookup(syserr_tbl, NUM2LONG(error), &klass)) {
            /* change class */
            if (TYPE(self) != T_OBJECT) { /* insurance to avoid type crash */
                rb_raise(rb_eTypeError, "invalid instance type");
            RBASIC(self)->klass = klass;
    else {
        rb_scan_args(argc, argv, "01", &mesg);
        error = rb_const_get(klass, rb_intern("Errno"));
    if (!NIL_P(error)) err = strerror(NUM2LONG(error));
    else err = "unknown error";
    if (!NIL_P(mesg)) {
        VALUE str = mesg;
        size_t len;

        len = strlen(err)+RSTRING(str)->len+3;
        mesg = rb_str_new(0, len);
        snprintf(RSTRING(mesg)->ptr, len+1, "%s - %.*s", err,
                (int)RSTRING(str)->len, RSTRING(str)->ptr);
        rb_str_resize(mesg, strlen(RSTRING(mesg)->ptr));
    else {
        mesg = rb_str_new2(err);
    rb_call_super(1, &mesg);
    rb_iv_set(self, "errno", error);
    return self;

Public Instance Methods

errno => fixnum click to toggle source

Return this SystemCallError’s error number.

               static VALUE
    VALUE self;
    return rb_attr_get(self, rb_intern("errno"));

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