Input and output

The <#1091#><#1091#> states that ports represent input and output devices. However, it defines only ports which are attached to files. In <#1092#><#1092#>, ports can also be attached to strings or to a external command input or output. String ports are similar to file ports, except that characters are read from (or written to) a string rather than a file. External command input or output ports are implemented with Unix pipes and are called pipe ports. A pipe port is created by specifying the command to execute prefixed with the string <#1093#>;SPMquot;|~;SPMquot;<#1093#>. Specification of a pipe port can occur everywhere a file name is needed.


#entry1094#


#entry1106#


#entry1116#


#entry1126#


#entry1134#


#entry1145#


#entry1153#


#entry1158#


#entry1174#


#entry1187#


#entry1198#


#entry1210#


#entry1216#


#entry1221#


#entry1229#


#entry1237#


#entry1263#


#entry1274#


#entry1300#


#entry1336#


#entry1344#


#entry1355#


#entry1378#


#entry1394#


#entry1404#


#entry1414#


#entry1423#


#entry1431#


#entry1450#


#entry1459#


#entry1470#


#entry1477#


#entry1486#