+\fI$HOME/.terminfo\fP database unless \fI\%TERMINFO\fP is explicitly set
+to it.
+.SH PORTABILITY
+X/Open Curses, Issue 7 (2009) provides a brief description of \fBtic\fP.
+It lists one option: \fB\-c\fP.
+The omission of \fB\-v\fP is unexpected.
+The change history states that the description is derived from Tru64.
+According to its manual pages, that system also supported the \fB\-v\fP option.
+.PP
+Shortly after Issue 7 was released, Tru64 was discontinued.
+As of 2019, the surviving implementations of \fBtic\fP
+are SVr4 (AIX, HP-UX and Solaris),
+\fI\%ncurses\fP
+and NetBSD curses.
+The SVr4 \fBtic\fP programs all support the \fB\-v\fP option.
+The NetBSD \fBtic\fP program follows X/Open's documentation,
+omitting the \fB\-v\fP option.
+.PP
+The X/Open rationale states that some implementations of \fBtic\fP
+read terminal descriptions from the standard input if the \fIfile\fP
+parameter is omitted.
+None of these implementations do that.
+Further, it comments that some may choose to read from \*(''./terminfo.src\*(''
+but that is obsolescent behavior from SVr2,
+and is not (for example) a documented feature of SVr3.
+.SH HISTORY
+System V Release 2 provided a \fBtic\fP utility.
+It accepted a single option: \fB\-v\fP (optionally followed by a number).
+According to Ross Ridge's comment in \fImytinfo\fP,
+this version of \fBtic\fP was
+unable to represent cancelled capabilities.
+.PP
+System V Release 3 provided a different \fBtic\fP utility,
+written by Pavel Curtis,
+(originally named \*(``compile\*('' in \fIpcurses\fP).
+This added an option \fB\-c\fP to check the file for
+errors, with the caveat that errors in \*(``use=\*('' links
+would not be reported.
+System V Release 3 documented a few warning messages which
+did not appear in \fIpcurses\fP.
+While the program itself was changed little as development
+continued with System V Release 4,
+the table of capabilities grew from 180 (\fIpcurses\fP) to 464 (Solaris).
+.PP
+In early development of \fI\%ncurses\fP (1993),
+Zeyd Ben-Halim used the table from \fImytinfo\fP to
+extend the \fIpcurses\fP table to 469 capabilities
+(456 matched SVr4, 8 were only in SVr4, 13 were not in SVr4).
+Of those 13, 11 were ultimately discarded
+(perhaps to match the draft of X/Open Curses).
+The exceptions were
+\fB\%memory_lock_above\fP and
+\fB\%memory_unlock\fP (see \fB\%user_caps\fP(5)).
+.PP
+Eric Raymond incorporated parts of \fImytinfo\fP into \fI\%ncurses\fP
+to implement the termcap-to-terminfo source conversion,
+and extended that to begin development of
+the corresponding terminfo-to-termcap source conversion,
+Thomas Dickey completed that development over the course of several years.
+.PP
+In 1999, Thomas Dickey added the \fB\-x\fP option
+to support user-defined capabilities.
+.PP
+In 2010, Roy Marples provided a \fBtic\fP program
+and terminfo library for NetBSD.
+That implementation adapts several features from \fI\%ncurses\fP,
+including \fB@TIC@\fP's \fB\-x\fP option.