# node:constants # `node:constants` ## Import ```js import constants from "nstdlib/constants"; ``` > [!NOTE] > Its behavior matches Node.js. Details: every constant compared by value against the host builtin. The one difference is `defaultCipherList`, which real Node also has once `crypto` has been loaded first. ## Runtime support | Where it runs | Status | Export coverage | Details | | ------------- | ------ | --------------- | ------- | | **nstd** | ✅ works | – | 1/1 of Node's own eligible tests pass under nstd. | | **Browser** | ❔ not tested | 100% of Node.js | It imports with the small process shim. 235/235 Node.js exports are available. No module-specific behavior test ran. | | **Node.js (host)** | ✅ works | 100% of Node.js | 235/235 exports. | ## Exports (235 of 235) Each cell shows what happens when code reads an export: - ✅ Available through every import style. A named error also counts. - ⚠️ Available through only some import styles. - ❔ The export exists but has no value. - ❌ The export does not exist. - – This environment was not measured.

Show all 236 exports

| Export | Node.js | nstdlib | browser | | ------ | ------- | ------- | ------- | | `COPYFILE_EXCL` | ✅ | ✅ | ✅ | | `COPYFILE_FICLONE` | ✅ | ✅ | ✅ | | `COPYFILE_FICLONE_FORCE` | ✅ | ✅ | ✅ | | `DH_CHECK_P_NOT_PRIME` | ✅ | ✅ | ✅ | | `DH_CHECK_P_NOT_SAFE_PRIME` | ✅ | ✅ | ✅ | | `DH_NOT_SUITABLE_GENERATOR` | ✅ | ✅ | ✅ | | `DH_UNABLE_TO_CHECK_GENERATOR` | ✅ | ✅ | ✅ | | `E2BIG` | ✅ | ✅ | ✅ | | `EACCES` | ✅ | ✅ | ✅ | | `EADDRINUSE` | ✅ | ✅ | ✅ | | `EADDRNOTAVAIL` | ✅ | ✅ | ✅ | | `EAFNOSUPPORT` | ✅ | ✅ | ✅ | | `EAGAIN` | ✅ | ✅ | ✅ | | `EALREADY` | ✅ | ✅ | ✅ | | `EBADF` | ✅ | ✅ | ✅ | | `EBADMSG` | ✅ | ✅ | ✅ | | `EBUSY` | ✅ | ✅ | ✅ | | `ECANCELED` | ✅ | ✅ | ✅ | | `ECHILD` | ✅ | ✅ | ✅ | | `ECONNABORTED` | ✅ | ✅ | ✅ | | `ECONNREFUSED` | ✅ | ✅ | ✅ | | `ECONNRESET` | ✅ | ✅ | ✅ | | `EDEADLK` | ✅ | ✅ | ✅ | | `EDESTADDRREQ` | ✅ | ✅ | ✅ | | `EDOM` | ✅ | ✅ | ✅ | | `EDQUOT` | ✅ | ✅ | ✅ | | `EEXIST` | ✅ | ✅ | ✅ | | `EFAULT` | ✅ | ✅ | ✅ | | `EFBIG` | ✅ | ✅ | ✅ | | `EHOSTUNREACH` | ✅ | ✅ | ✅ | | `EIDRM` | ✅ | ✅ | ✅ | | `EILSEQ` | ✅ | ✅ | ✅ | | `EINPROGRESS` | ✅ | ✅ | ✅ | | `EINTR` | ✅ | ✅ | ✅ | | `EINVAL` | ✅ | ✅ | ✅ | | `EIO` | ✅ | ✅ | ✅ | | `EISCONN` | ✅ | ✅ | ✅ | | `EISDIR` | ✅ | ✅ | ✅ | | `ELOOP` | ✅ | ✅ | ✅ | | `EMFILE` | ✅ | ✅ | ✅ | | `EMLINK` | ✅ | ✅ | ✅ | | `EMSGSIZE` | ✅ | ✅ | ✅ | | `EMULTIHOP` | ✅ | ✅ | ✅ | | `ENAMETOOLONG` | ✅ | ✅ | ✅ | | `ENETDOWN` | ✅ | ✅ | ✅ | | `ENETRESET` | ✅ | ✅ | ✅ | | `ENETUNREACH` | ✅ | ✅ | ✅ | | `ENFILE` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_ALL` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_CIPHERS` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_DH` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_DIGESTS` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_DSA` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_EC` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_NONE` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_PKEY_ASN1_METHS` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_PKEY_METHS` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_RAND` | ✅ | ✅ | ✅ | | `ENGINE_METHOD_RSA` | ✅ | ✅ | ✅ | | `ENOBUFS` | ✅ | ✅ | ✅ | | `ENODATA` | ✅ | ✅ | ✅ | | `ENODEV` | ✅ | ✅ | ✅ | | `ENOENT` | ✅ | ✅ | ✅ | | `ENOEXEC` | ✅ | ✅ | ✅ | | `ENOLCK` | ✅ | ✅ | ✅ | | `ENOLINK` | ✅ | ✅ | ✅ | | `ENOMEM` | ✅ | ✅ | ✅ | | `ENOMSG` | ✅ | ✅ | ✅ | | `ENOPROTOOPT` | ✅ | ✅ | ✅ | | `ENOSPC` | ✅ | ✅ | ✅ | | `ENOSR` | ✅ | ✅ | ✅ | | `ENOSTR` | ✅ | ✅ | ✅ | | `ENOSYS` | ✅ | ✅ | ✅ | | `ENOTCONN` | ✅ | ✅ | ✅ | | `ENOTDIR` | ✅ | ✅ | ✅ | | `ENOTEMPTY` | ✅ | ✅ | ✅ | | `ENOTSOCK` | ✅ | ✅ | ✅ | | `ENOTSUP` | ✅ | ✅ | ✅ | | `ENOTTY` | ✅ | ✅ | ✅ | | `ENXIO` | ✅ | ✅ | ✅ | | `EOPNOTSUPP` | ✅ | ✅ | ✅ | | `EOVERFLOW` | ✅ | ✅ | ✅ | | `EPERM` | ✅ | ✅ | ✅ | | `EPIPE` | ✅ | ✅ | ✅ | | `EPROTO` | ✅ | ✅ | ✅ | | `EPROTONOSUPPORT` | ✅ | ✅ | ✅ | | `EPROTOTYPE` | ✅ | ✅ | ✅ | | `ERANGE` | ✅ | ✅ | ✅ | | `EROFS` | ✅ | ✅ | ✅ | | `ESPIPE` | ✅ | ✅ | ✅ | | `ESRCH` | ✅ | ✅ | ✅ | | `ESTALE` | ✅ | ✅ | ✅ | | `ETIME` | ✅ | ✅ | ✅ | | `ETIMEDOUT` | ✅ | ✅ | ✅ | | `ETXTBSY` | ✅ | ✅ | ✅ | | `EWOULDBLOCK` | ✅ | ✅ | ✅ | | `EXDEV` | ✅ | ✅ | ✅ | | `F_OK` | ✅ | ✅ | ✅ | | `OPENSSL_VERSION_NUMBER` | ✅ | ✅ | ✅ | | `O_APPEND` | ✅ | ✅ | ✅ | | `O_CREAT` | ✅ | ✅ | ✅ | | `O_DIRECT` | ✅ | ✅ | ✅ | | `O_DIRECTORY` | ✅ | ✅ | ✅ | | `O_DSYNC` | ✅ | ✅ | ✅ | | `O_EXCL` | ✅ | ✅ | ✅ | | `O_NOATIME` | ✅ | ✅ | ✅ | | `O_NOCTTY` | ✅ | ✅ | ✅ | | `O_NOFOLLOW` | ✅ | ✅ | ✅ | | `O_NONBLOCK` | ✅ | ✅ | ✅ | | `O_RDONLY` | ✅ | ✅ | ✅ | | `O_RDWR` | ✅ | ✅ | ✅ | | `O_SYNC` | ✅ | ✅ | ✅ | | `O_TRUNC` | ✅ | ✅ | ✅ | | `O_WRONLY` | ✅ | ✅ | ✅ | | `POINT_CONVERSION_COMPRESSED` | ✅ | ✅ | ✅ | | `POINT_CONVERSION_HYBRID` | ✅ | ✅ | ✅ | | `POINT_CONVERSION_UNCOMPRESSED` | ✅ | ✅ | ✅ | | `PRIORITY_ABOVE_NORMAL` | ✅ | ✅ | ✅ | | `PRIORITY_BELOW_NORMAL` | ✅ | ✅ | ✅ | | `PRIORITY_HIGH` | ✅ | ✅ | ✅ | | `PRIORITY_HIGHEST` | ✅ | ✅ | ✅ | | `PRIORITY_LOW` | ✅ | ✅ | ✅ | | `PRIORITY_NORMAL` | ✅ | ✅ | ✅ | | `RSA_NO_PADDING` | ✅ | ✅ | ✅ | | `RSA_PKCS1_OAEP_PADDING` | ✅ | ✅ | ✅ | | `RSA_PKCS1_PADDING` | ✅ | ✅ | ✅ | | `RSA_PKCS1_PSS_PADDING` | ✅ | ✅ | ✅ | | `RSA_PSS_SALTLEN_AUTO` | ✅ | ✅ | ✅ | | `RSA_PSS_SALTLEN_DIGEST` | ✅ | ✅ | ✅ | | `RSA_PSS_SALTLEN_MAX_SIGN` | ✅ | ✅ | ✅ | | `RSA_SSLV23_PADDING` | ✅ | ✅ | ✅ | | `RSA_X931_PADDING` | ✅ | ✅ | ✅ | | `RTLD_DEEPBIND` | ✅ | ✅ | ✅ | | `RTLD_GLOBAL` | ✅ | ✅ | ✅ | | `RTLD_LAZY` | ✅ | ✅ | ✅ | | `RTLD_LOCAL` | ✅ | ✅ | ✅ | | `RTLD_NOW` | ✅ | ✅ | ✅ | | `R_OK` | ✅ | ✅ | ✅ | | `SIGABRT` | ✅ | ✅ | ✅ | | `SIGALRM` | ✅ | ✅ | ✅ | | `SIGBUS` | ✅ | ✅ | ✅ | | `SIGCHLD` | ✅ | ✅ | ✅ | | `SIGCONT` | ✅ | ✅ | ✅ | | `SIGFPE` | ✅ | ✅ | ✅ | | `SIGHUP` | ✅ | ✅ | ✅ | | `SIGILL` | ✅ | ✅ | ✅ | | `SIGINT` | ✅ | ✅ | ✅ | | `SIGIO` | ✅ | ✅ | ✅ | | `SIGIOT` | ✅ | ✅ | ✅ | | `SIGKILL` | ✅ | ✅ | ✅ | | `SIGPIPE` | ✅ | ✅ | ✅ | | `SIGPOLL` | ✅ | ✅ | ✅ | | `SIGPROF` | ✅ | ✅ | ✅ | | `SIGPWR` | ✅ | ✅ | ✅ | | `SIGQUIT` | ✅ | ✅ | ✅ | | `SIGSEGV` | ✅ | ✅ | ✅ | | `SIGSTKFLT` | ✅ | ✅ | ✅ | | `SIGSTOP` | ✅ | ✅ | ✅ | | `SIGSYS` | ✅ | ✅ | ✅ | | `SIGTERM` | ✅ | ✅ | ✅ | | `SIGTRAP` | ✅ | ✅ | ✅ | | `SIGTSTP` | ✅ | ✅ | ✅ | | `SIGTTIN` | ✅ | ✅ | ✅ | | `SIGTTOU` | ✅ | ✅ | ✅ | | `SIGURG` | ✅ | ✅ | ✅ | | `SIGUSR1` | ✅ | ✅ | ✅ | | `SIGUSR2` | ✅ | ✅ | ✅ | | `SIGVTALRM` | ✅ | ✅ | ✅ | | `SIGWINCH` | ✅ | ✅ | ✅ | | `SIGXCPU` | ✅ | ✅ | ✅ | | `SIGXFSZ` | ✅ | ✅ | ✅ | | `SSL_OP_ALL` | ✅ | ✅ | ✅ | | `SSL_OP_ALLOW_NO_DHE_KEX` | ✅ | ✅ | ✅ | | `SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION` | ✅ | ✅ | ✅ | | `SSL_OP_CIPHER_SERVER_PREFERENCE` | ✅ | ✅ | ✅ | | `SSL_OP_CISCO_ANYCONNECT` | ✅ | ✅ | ✅ | | `SSL_OP_COOKIE_EXCHANGE` | ✅ | ✅ | ✅ | | `SSL_OP_CRYPTOPRO_TLSEXT_BUG` | ✅ | ✅ | ✅ | | `SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS` | ✅ | ✅ | ✅ | | `SSL_OP_LEGACY_SERVER_CONNECT` | ✅ | ✅ | ✅ | | `SSL_OP_NO_COMPRESSION` | ✅ | ✅ | ✅ | | `SSL_OP_NO_ENCRYPT_THEN_MAC` | ✅ | ✅ | ✅ | | `SSL_OP_NO_QUERY_MTU` | ✅ | ✅ | ✅ | | `SSL_OP_NO_RENEGOTIATION` | ✅ | ✅ | ✅ | | `SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION` | ✅ | ✅ | ✅ | | `SSL_OP_NO_SSLv2` | ✅ | ✅ | ✅ | | `SSL_OP_NO_SSLv3` | ✅ | ✅ | ✅ | | `SSL_OP_NO_TICKET` | ✅ | ✅ | ✅ | | `SSL_OP_NO_TLSv1` | ✅ | ✅ | ✅ | | `SSL_OP_NO_TLSv1_1` | ✅ | ✅ | ✅ | | `SSL_OP_NO_TLSv1_2` | ✅ | ✅ | ✅ | | `SSL_OP_NO_TLSv1_3` | ✅ | ✅ | ✅ | | `SSL_OP_PRIORITIZE_CHACHA` | ✅ | ✅ | ✅ | | `SSL_OP_TLS_ROLLBACK_BUG` | ✅ | ✅ | ✅ | | `S_IFBLK` | ✅ | ✅ | ✅ | | `S_IFCHR` | ✅ | ✅ | ✅ | | `S_IFDIR` | ✅ | ✅ | ✅ | | `S_IFIFO` | ✅ | ✅ | ✅ | | `S_IFLNK` | ✅ | ✅ | ✅ | | `S_IFMT` | ✅ | ✅ | ✅ | | `S_IFREG` | ✅ | ✅ | ✅ | | `S_IFSOCK` | ✅ | ✅ | ✅ | | `S_IRGRP` | ✅ | ✅ | ✅ | | `S_IROTH` | ✅ | ✅ | ✅ | | `S_IRUSR` | ✅ | ✅ | ✅ | | `S_IRWXG` | ✅ | ✅ | ✅ | | `S_IRWXO` | ✅ | ✅ | ✅ | | `S_IRWXU` | ✅ | ✅ | ✅ | | `S_IWGRP` | ✅ | ✅ | ✅ | | `S_IWOTH` | ✅ | ✅ | ✅ | | `S_IWUSR` | ✅ | ✅ | ✅ | | `S_IXGRP` | ✅ | ✅ | ✅ | | `S_IXOTH` | ✅ | ✅ | ✅ | | `S_IXUSR` | ✅ | ✅ | ✅ | | `TLS1_1_VERSION` | ✅ | ✅ | ✅ | | `TLS1_2_VERSION` | ✅ | ✅ | ✅ | | `TLS1_3_VERSION` | ✅ | ✅ | ✅ | | `TLS1_VERSION` | ✅ | ✅ | ✅ | | `UV_DIRENT_BLOCK` | ✅ | ✅ | ✅ | | `UV_DIRENT_CHAR` | ✅ | ✅ | ✅ | | `UV_DIRENT_DIR` | ✅ | ✅ | ✅ | | `UV_DIRENT_FIFO` | ✅ | ✅ | ✅ | | `UV_DIRENT_FILE` | ✅ | ✅ | ✅ | | `UV_DIRENT_LINK` | ✅ | ✅ | ✅ | | `UV_DIRENT_SOCKET` | ✅ | ✅ | ✅ | | `UV_DIRENT_UNKNOWN` | ✅ | ✅ | ✅ | | `UV_FS_COPYFILE_EXCL` | ✅ | ✅ | ✅ | | `UV_FS_COPYFILE_FICLONE` | ✅ | ✅ | ✅ | | `UV_FS_COPYFILE_FICLONE_FORCE` | ✅ | ✅ | ✅ | | `UV_FS_O_FILEMAP` | ✅ | ✅ | ✅ | | `UV_FS_SYMLINK_DIR` | ✅ | ✅ | ✅ | | `UV_FS_SYMLINK_JUNCTION` | ✅ | ✅ | ✅ | | `W_OK` | ✅ | ✅ | ✅ | | `X_OK` | ✅ | ✅ | ✅ | | `defaultCipherList` | ❌ | ✅ | ✅ | | `defaultCoreCipherList` | ✅ | ✅ | ✅ |