xref: /freebsd/lib/libcompat/4.3/re_comp.3 (revision 230f8c40e55e3462e90151e30f61bd0fdd4dcda3)
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32.\"     @(#)re_comp.3	8.1 (Berkeley) 6/4/93
33.\"
34.Dd June 4, 1993
35.Dt RE_COMP 3
36.Os
37.Sh NAME
38.Nm re_comp ,
39.Nm re_exec
40.Nd regular expression handler
41.Sh SYNOPSIS
42.Fd #include <unistd.h>
43.Ft char *
44.Fn re_comp "const char *s"
45.Ft int
46.Fn re_exec "const char *s"
47.Sh DESCRIPTION
48This interface is made obsolete by
49.Xr regex 3 .
50It is available from the compatibility library, libcompat.
51.Pp
52The
53.Fn re_comp
54function
55compiles a string into an internal form suitable for pattern matching.
56The
57.Fn re_exec
58function
59checks the argument string against the last string passed to
60.Fn re_comp .
61.Pp
62The
63.Fn re_comp
64function
65returns 0 if the string
66.Fa s
67was compiled successfully; otherwise a string containing an
68error message is returned. If
69.Fn re_comp
70is passed 0 or a null string, it returns without changing the currently
71compiled regular expression.
72.Pp
73The
74.Fn re_exec
75function
76returns 1 if the string
77.Fa s
78matches the last compiled regular expression, 0 if the string
79.Fa s
80failed to match the last compiled regular expression, and \-1 if the compiled
81regular expression was invalid (indicating an internal error).
82.Pp
83The strings passed to both
84.Fn re_comp
85and
86.Fn re_exec
87may have trailing or embedded newline characters;
88they are terminated by
89.Dv NUL Ns s.
90The regular expressions recognized are described in the manual entry for
91.Xr ed 1 ,
92given the above difference.
93.Sh DIAGNOSTICS
94The
95.Fn re_exec
96function
97returns \-1 for an internal error.
98.Pp
99The
100.Fn re_comp
101function
102returns one of the following strings if an error occurs:
103.Bd -unfilled -offset indent
104No previous regular expression,
105Regular expression too long,
106unmatched \e(,
107missing ],
108too many \e(\e) pairs,
109unmatched \e).
110.Ed
111.Sh SEE ALSO
112.Xr ed 1 ,
113.Xr egrep 1 ,
114.Xr ex 1 ,
115.Xr fgrep 1 ,
116.Xr grep 1 ,
117.Xr regex 3
118.Sh HISTORY
119The
120.Fn re_comp
121and
122.Fn re_exec
123functions appeared in
124.Bx 4.0 .
125