NAME
len - predefined operator to determine the number of messages stored in a channel.

SYNTAX
len( varref )

DESCRIPTION
A predefined unary operator that takes the name of a channel as an operand and returns the number of messages that it currently holds.

EXAMPLES

chan q = [4] of { mtype, short };



len(q) >  0	/* same as nempty(q) */

len(q) == 0	/* same as empty(q) */

len(q) == 4	/* same as full(q) */

len(q) <  4	/* same as nfull(q) */

NOTES
If len is used as a condition statement, rather than on the right side of an assignment, it is unexecutable if the channel is empty.

SEE ALSO
empty(5), full(5), nempty(5), nfull(5).