evbuffer_find.3

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.Dd $Mdocdate$
.Dt EVBUFFER_FIND 3
.Os
.Sh NAME
.Nm evbuffer_find
.Nd search an evbuffer for a byte sequence
.Sh SYNOPSIS
.In sys/types.h
.In event.h
.Ft "u_char *"
.Fn evbuffer_find "struct evbuffer *buf" "const u_char *what" "size_t len"
.Sh DESCRIPTION
This function locates the first occurrence of byte sequence
.Fa what
in the
.Vt evbuffer
structure
.Fa buf .
The number of bytes in the sequence is denoted by the the argument
.Fa len .
.Pp
If either
.Fa buf
or
.Fa what
is
.Dv NULL
or the buffer is empty, the function causes undefined behavior.
If the value of
.Fa len
is zero, it signifies an empty byte sequence.
This is an invalid input for searching within the buffer.
.Sh RETURN VALUES
.Fn evbuffer_find
returns a pointer to the first occurrence of the specified byte sequence
within the
.Vt evbuffer .
If the sequence is not found or
.Fa len
is zero, the function returns NULL.
.Pp
The returned pointer remains valid if and only if the buffer is unmodified.
.\" .Sh EXAMPLES
.Sh SEE ALSO
.Xr evbuffer_add 3 ,
.Xr evbuffer_new 3
.Sh HISTORY
This function first appeared in libevent-0.8 and has been available since
.Ox 3.6 .
.Sh AUTHORS
.Fn evbuffer_find
was written by
.An -nosplit
.An Niels Provos .
.Pp
This manual page was written by
.An Ted Bullock Aq Mt tbullock@comlore.com .
.Sh CAVEATS
.Fn evbuffer_find
returns a pointer to an internal array within the
.Vt evbuffer
structure.
This behavior is not a promised feature of the evbuffer API.