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class method

File.writable_real?

File.writable_real?(file_name) → true or false

static VALUE
rb_file_writable_real_p(VALUE obj, VALUE fname)
{
    return RBOOL(rb_access(fname, W_OK) >= 0);
}

Returns true if the named file is writable by the real user and group id of this process. See access(3).

Note that some OS-level security features may cause this to return true even though the file is not writable by the real user/group.

See also .writable? .zero? .world_writable? #atime also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.0