The LINESPECIALINFO_ bit-flag constants describes special information signals
that the network may use to report various reporting and network observation
operations. They are special coded tone sequences transmitted at the beginning of
network advisory recorded announcements.
This special information tone precedes a no circuit or an emergency
announcement (trunk blockage category).
This special information tone precedes a vacant number, AIS, Centrex number
change and nonworking station, access code not dialed or dialed in error, or
manual intercept operator message (customer irregularity category).
LINESPECIALINFO_CUSTIRREG is also reported when billing information is rejected and when the
dialed address is blocked at the switch.
This special information tone precedes a reorder announcement (equipment
irregularity category). LINESPECIALINFO_REORDER is also reported when the telephone
is kept offhook too long.
Specifics about the special information tone are currently unknown but may
become known later.
Specifics about the special information tone are unavailable and will not
The high-order 16 bits can be assigned for device-specific extensions. The
low-order 16 bits are reserved.
Special information tones are defined for advisory messages and are not
normally used for billing or supervisory purpose.
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