+.PP
+The BSD termcap function \fBtgetent\fP returns the text of a termcap
+entry in the buffer passed as an argument.
+This library (like other terminfo implementations) does not store
+terminal descriptions as text.
+It sets the buffer contents to a null-terminated string.
+.SS Other Compatibility
+This library includes a termcap.h header,
+for compatibility with other implementations.
+But the header is rarely used because the other implementations
+are not strictly compatible.
+.PP
+The original BSD termcap (through 4.3BSD) had no header file which
+gave function prototypes, because that was a feature of ANSI C.
+BSD termcap was written several years before C was standardized.
+However, there were two different termcap.h header files in the BSD
+sources:
+.bP
+One was used internally by the \fIjove\fP editor in 2BSD through 4.4BSD.
+It defined global symbols for the termcap variables which it used.
+.bP
+The other appeared in 4.4BSD Lite Release 2 (mid-1993)
+as part of \fIlibedit\fP (also known as the \fIeditline\fP library).
+The CSRG source history shows that this was added in mid-1992.
+The \fIlibedit\fP header file was used internally,
+as a convenience for compiling the \fIeditline\fP library.
+It declared function prototypes, but no global variables.
+.PP
+The header file from \fIlibedit\fP was added to NetBSD's termcap
+library in mid-1994.
+.PP
+Meanwhile, GNU termcap was under development, starting in 1990.
+The first release (termcap 1.0) in 1991 included a termcap.h header.
+The second release (termcap 1.1) in September 1992 modified the
+header to use \fBconst\fP for the function prototypes in the header
+where one would expect the parameters to be read-only.
+This was a difference versus the original BSD termcap.
+The prototype for \fBtputs\fP also differed,
+but in that instance, it was \fIlibedit\fP which differed from BSD termcap.
+.PP
+A copy of GNU termcap 1.3 was bundled with \fIbash\fP in mid-1993,
+to support the \fIreadline\fP library.
+.PP
+A termcap.h file was provided in ncurses 1.8.1 (November 1993).
+That reflected influence by \fIemacs\fP (rather than \fIjove\fP)
+and GNU termcap:
+.bP
+it provided declarations for a few global symbols used by \fIemacs\fP
+.bP
+it provided function prototypes (using \fBconst\fP).
+.bP
+a prototype for \fBtparam\fP (a GNU termcap feature) was provided.
+.PP
+Later (in mid-1996) the \fBtparam\fP function was removed from ncurses.
+As a result, there are differences between any of the four implementations,
+which must be taken into account by programs which can work with all
+termcap library interfaces.
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