msgappend

msgappend ?-cvtnull char? msgId data

This command appends the specified data to msgId. If the -cvtnull option is used, then every instance of char is converted to a null character before the data is appended to the message.

This command returns an empty string.

msgappread ?-stats statsVar? len10 msgId fileId
msgappread ?-stats statsVar? nl msgId fileId
msgappread ?-stats statsVar? raw msgId fileId len

This command reads the next message from fileId, an open file handle. It then appends the data to msgId.

If a len10 or nl read is specified, then the appropriate message boundary is used to terminate the read.

Supply a read length, len, for raw reads.

If a statsVar variable name is supplied, then the variable is set to contain a list of two values: todo done.

  • todo is the number of bytes requested. This is the length implied by a len10 record header: 0 for nl reads, or the len value for raw reads.
  • done is the actual number of characters read.

These values can be useful when a read fails.

This command returns the number of bytes read.