Exception: SystemCallError
| Relationships & Source Files | |
| Super Chains via Extension / Inclusion / Inheritance | |
| Class Chain: 
          self,
           ::StandardError,::Exception | |
| Instance Chain: 
          self,
           ::StandardError,::Exception | |
| Inherits: | StandardError 
 | 
| Defined in: | error.c, error.c | 
Overview
SystemCallError is the base class for all low-level platform-dependent errors.
The errors available on the current platform are subclasses of SystemCallError and are defined in the ::Errno module.
File.open("does/not/exist")raises the exception:
Errno::ENOENT: No such file or directory - does/not/existClass Attribute Summary
::Exception - Inherited
| .to_tty? | Returns  | 
Class Method Summary
- 
    
      .===(other)  ⇒ Boolean 
    
    Return trueif the receiver is a genericSystemCallError, or if the error numbersselfand other are the same.
- 
    
      .new(msg, errno)  ⇒ system_call_error_subclass 
    
    constructor
    If errno corresponds to a known system error code, constructs the appropriate ::Errnoclass for that error, otherwise constructs a genericSystemCallErrorobject.
::Exception - Inherited
| .exception | With no argument, or if the argument is the same as the receiver, return the receiver. | 
| .new | Construct a new  | 
Instance Method Summary
- 
    
      #errno  ⇒ Integer 
    
    Return this SystemCallError’s error number. 
::Exception - Inherited
| #== | Equality—If obj is not an  | 
| #backtrace | Returns any backtrace associated with the exception. | 
| #backtrace_locations | Returns any backtrace associated with the exception. | 
| #cause | Returns the previous exception ($!) at the time this exception was raised. | 
| #exception | With no argument, or if the argument is the same as the receiver, return the receiver. | 
| #full_message | Returns formatted string of exception. | 
| #inspect | Return this exception’s class name and message. | 
| #message | Returns the result of invoking  | 
| #set_backtrace | Sets the backtrace information associated with  | 
| #to_s | Returns exception’s message (or the name of the exception if no message is set). | 
Constructor Details
    .new(msg, errno)  ⇒ system_call_error_subclass   
# File 'error.c', line 2343
static VALUE
syserr_initialize(int argc, VALUE *argv, VALUE self)
{
#if !defined(_WIN32)
    char *strerror();
#endif
    const char *err;
    VALUE mesg, error, func, errmsg;
    VALUE klass = rb_obj_class(self);
    if (klass == rb_eSystemCallError) {
	st_data_t data = (st_data_t)klass;
	rb_scan_args(argc, argv, "12", &mesg, &error, &func);
	if (argc == 1 && FIXNUM_P(mesg)) {
	    error = mesg; mesg = Qnil;
	}
	if (!NIL_P(error) && st_lookup(syserr_tbl, NUM2LONG(error), &data)) {
	    klass = (VALUE)data;
	    /* change class */
	    if (!RB_TYPE_P(self, T_OBJECT)) { /* insurance to avoid type crash */
		rb_raise(rb_eTypeError, "invalid instance type");
	    }
	    RBASIC_SET_CLASS(self, klass);
	}
    }
    else {
	rb_scan_args(argc, argv, "02", &mesg, &func);
	error = rb_const_get(klass, id_Errno);
    }
    if (!NIL_P(error)) err = strerror(NUM2INT(error));
    else err = "unknown error";
    errmsg = rb_enc_str_new_cstr(err, rb_locale_encoding());
    if (!NIL_P(mesg)) {
	VALUE str = StringValue(mesg);
	if (!NIL_P(func)) rb_str_catf(errmsg, " @ %"PRIsVALUE, func);
	rb_str_catf(errmsg, " - %"PRIsVALUE, str);
    }
    mesg = errmsg;
    rb_call_super(1, &mesg);
    rb_ivar_set(self, id_errno, error);
    return self;
}
  Class Method Details
    .===(other)  ⇒ Boolean   
Return true if the receiver is a generic SystemCallError, or if the error numbers self and other are the same.
# File 'error.c', line 2410
static VALUE
syserr_eqq(VALUE self, VALUE exc)
{
    VALUE num, e;
    if (!rb_obj_is_kind_of(exc, rb_eSystemCallError)) {
	if (!rb_respond_to(exc, id_errno)) return Qfalse;
    }
    else if (self == rb_eSystemCallError) return Qtrue;
    num = rb_attr_get(exc, id_errno);
    if (NIL_P(num)) {
	num = rb_funcallv(exc, id_errno, 0, 0);
    }
    e = rb_const_get(self, id_Errno);
    return RBOOL(FIXNUM_P(num) ? num == e : rb_equal(num, e));
}
  Instance Method Details
#errno ⇒ Integer
Return this SystemCallError’s error number.
# File 'error.c', line 2396
static VALUE
syserr_errno(VALUE self)
{
    return rb_attr_get(self, id_errno);
}