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HELP DISCIN Steven Hardy, January 1978 Revised by John Williams, May 1993 discin(file_name) -> char_rep The procedure discin takes a file name as argument, and returns a character repeater procedure (analogous to * charin), which reads characters one at a time from the given file. For example: discin('myfile.p') -> rep; This creates a character repeater procedure for the file 'myfile.p' and assigns it to the variable "rep". Successive calls of "rep", i.e. rep() -> char; return successive characters from the file 'myfile.p'. The special object * termin is returned when the end of the file is reached. If the file name given to discin is a word, the value of the variable * pop_default_type (normally '.p') is appended to that word, so discin("myfile") and discin('myfile.p') are equivalent. discin can also be given a * DEVICE record as argument, in which case a procedure that reads successive characters from that device is created. The underlying device record associated with a character repeater produced by discin can be accessed with the procedure * discin_device. This can be useful if you want to test for input on the device, or close it, for example. See REF * CHARIO for more details. See also: HELP * DISCOUT for creating character consumer procedures HELP * DEVICE introduction to Poplog "device" records HELP * INCHARITEM procedure for converting character repeaters to item repeaters REF * CHARIO reference guide to Poplog character stream i/o --- C.all/help/discin --- Copyright University of Sussex 1993. All rights reserved.