function
read_char
read_char() -> int
Reads a single byte from standard input and returns its value, or -1 when the input has ended. It is the foundation for headless, pipe-driven runs: a test or tool can feed the program a stream of bytes and process them one at a time, looping until read_char returns -1. Compare the byte against character literals such as 'a' to interpret it. It takes no arguments and advances through the input on each call.
Example
program CountInputBytes {
handler DrainInput phase Start {
var byte_count: int = 0
var next_byte = read_char()
while next_byte != -1 {
byte_count = byte_count + 1
next_byte = read_char()
}
print(byte_count)
}
}