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OpenIFile, OpenOFile

Syntax

OpenIFile(S:STRING):DEVICE
OpenOFile(S:STRING):DEVICE
OpenOFile(S:STRING,"w" or "W"):DEVICE
    

Summary

open input or output file

Description

These functions open files for input or output. OpenIFile opens the file with name S. Input from that file can then be read with Get. OpenOFile opens the file with name S---creating it if it does not already exist---for output. The function Print On is then used for writing output to the file. If OpenOFile is used without a second argument or if the second argument is not w or W then Print On will append output to the file. Otherwise, any existing file with the name S will be erased before the output is written.

(Note: one would normally use Source to read CoCoA commands from a file.)

example

    
D := OpenOFile("my-test");  -- open "my-test" for output from CoCoA
Print "hello world" On D;   -- print string into "mytest"
Print " test" On D;  -- append to the file "mytest"
Close(D);  -- close the file
D := OpenIFile("my-test");  -- open "my-test" for input to CoCoA
Get(D,3);  -- get the first three characters (in Ascii code)
[104, 101, 108]
-------------------------------
Ascii(It);  -- convert the ascii code into characters
hel
-------------------------------
Close(D);
D := OpenOFile("my-test","w"); -- clear "my-test"
Print "goodbye" On D; -- "mytest" now consists only of the string "goodbye"
Close(D);
        
    

See Also