Reads the specified number of characters from a file or the keyboard.
INPUT$(num_characters[,[#]file number])
num_characters is the number of characters for INPUT$ to read. It must be less than or equal to the record length of the file, which is 128 by default.
file_number is the number assigned to the file in its OPEN statement. If you omit a file number, INPUT$ reads from the keyboard.
If the keyboard is used for input, no characters will appear on the screen. All control characters (except CTRL-BREAK) are passed through. CTRL-BREAK interrupts the execution of the INPUT$ function.
The INPUT$ function is preferred over INPUT and LINE INPUT statements for reading communications files, because all ASCII characters may be significant in communications. INPUT is the least desirable because input stops when a comma or carriage return is seen. LINE INPUT terminates when a carriage return is seen.
INPUT$ allows all characters read to be assigned to a string. INPUT$ will return num_characters characters from the file number or keyboard.
For more information about communications, refer to Appendix F in the BASIC User’s Guide.
The following example lists the contents of a sequential file in hexadecimal.
'Display a file in UPPERCASE
OPEN "\CONFIG.SYS" FOR INPUT AS #1
DO WHILE NOT EOF(l)
char$ = INPUT$(1, 1)
PRINT UCASE$(char$):
LOOP
CLOSE #1