====== Function OPEN-STREAM-P ====== ====Syntax==== * **open-stream-p** //stream// → //generalized-boolean// ====Arguments and Values==== * //stream// - a //[[CL:Glossary:stream]]//. * //generalized-boolean// - a //[[CL:Glossary:generalized boolean]]//. ====Description==== Returns //[[CL:Glossary:true]]// if //stream// is an //[[CL:Glossary:open]]// //[[CL:Glossary:stream]]//; otherwise, returns //[[CL:Glossary:false]]//. //[[CL:Glossary:stream|Streams]]// are open until they have been explicitly closed with **[[CL:Functions:close]]**, or until they are implicitly closed due to exit from a **[[CL:Macros:with-output-to-string]]**, **[[CL:Macros:with-open-file]]**, **[[CL:Macros:with-input-from-string]]**, or **[[CL:Macros:with-open-stream]]** //[[CL:Glossary:form]]//. ====Examples==== <blockquote> (open-stream-p [[CL:Variables:star-standard-input-star|*standard-input*]]) → //[[CL:Glossary:true]]// </blockquote> ====Side Effects==== None. ====Affected By==== **[[CL:Functions:close]]**. ====Exceptional Situations==== Should signal an error of type type-error if //stream// is not a //[[CL:Glossary:stream]]//. ====See Also==== None. ====Notes==== None. \issue{STREAM-ACCESS:ADD-TYPES-ACCESSORS}