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FPARSELN(3)                Library Functions Manual                FPARSELN(3)

     fparseln - return the next logical line from a stream

     Standard C Library (libc, -lc)

     #include <stdio.h>

     char *
     fparseln(FILE *stream, size_t *len, size_t *lineno, const char delim[3],
         int flags);

     The fparseln() function returns a pointer to the next logical line from
     the stream referenced by stream.  This string is NUL terminated and it is
     dynamically allocated on each invocation.  It is the responsibility of
     the caller to free the pointer.

     By default, if a character is escaped, both it and the preceding escape
     character will be present in the returned string.  Various flags alter
     this behaviour.

     The meaning of the arguments is as follows:

     stream  The stream to read from.

     len     If not NULL, the length of the string is stored in the memory
             location to which it points.

     lineno  If not NULL, the value of the memory location to which is pointed
             to, is incremented by the number of lines actually read from the

     delim   Contains the escape, continuation, and comment characters.  If a
             character is NUL then processing for that character is disabled.
             If NULL, all characters default to values specified below.  The
             contents of delim is as follows:

             delim[0]  The escape character, which defaults to \, is used to
                       remove any special meaning from the next character.

             delim[1]  The continuation character, which defaults to \, is
                       used to indicate that the next line should be
                       concatenated with the current one if this character is
                       the last character on the current line and is not

             delim[2]  The comment character, which defaults to #, if not
                       escaped indicates the beginning of a comment that
                       extends until the end of the current line.

     flags   If non-zero, alter the operation of fparseln().  The various
             flags, which may be or-ed together, are:

             FPARSELN_UNESCCOMM  Remove escape preceding an escaped comment.

             FPARSELN_UNESCCONT  Remove escape preceding an escaped

             FPARSELN_UNESCESC   Remove escape preceding an escaped escape.

             FPARSELN_UNESCREST  Remove escape preceding any other character.

             FPARSELN_UNESCALL   All of the above.

     Upon successful completion a pointer to the parsed line is returned;
     otherwise, NULL is returned.

     The fparseln() function uses internally fgetln(3), so all error
     conditions that apply to fgetln(3), apply to fparseln().  In addition
     fparseln() may set errno to [ENOMEM] and return NULL if it runs out of


     The fparseln() function first appeared in NetBSD 1.4.

NetBSD 9.99                    November 30, 2002                   NetBSD 9.99