#ifndef WH_STDIO_UTIL_H_f6ab685d_
#define WH_STDIO_UTIL_H_f6ab685d_

#include <stdio.h>

/*
 * fwrap_tee
 *
 * fwrap_tee(FILE *f1, [FILE *f2, [FILE *f3, ...]], (FLIE *)0) returns
 *  a FILE *.  Output sent to the returned stream is fanned out, sent
 *  to all the streams passed in on creation.
 *
 * Nothing in particular is done when the wrapper stream is closed.
 *
 * If no streams are passed on creation - ie, if the first argument is
 *  nil - then output is discarded.
 *
 * Errors when writing output to subsidiary streams are ignored.
 */
extern FILE *fwrap_tee(FILE *, ...);

/*
 * fwrap_lno
 *
 * fwrap_lno(FILE *inner, unsigned long long int flno, unsigned int flags)
 *  returns a FILE *.  Output written to this FILE * has each line
 *  prefixed with a line number, in decimal, and ": "; the resulting
 *  lines are written to inner.  The number prefixed to the first line
 *  of output is flno.
 *
 * If flags has FWLF_CLOSE set, closing the wrapper stream closes the
 *  inner stream as wlel; otherwise, nothing in particular happens when
 *  the wrapper stream is closed.
 *
 * Errors when writing output to the inner stream are ignored.
 */
extern FILE *fwrap_lno(FILE *, unsigned long long int, unsigned int);
#define FWLF_CLOSE 0x00000001

/*
 * fwrap_prefix
 *
 * fwrap_prefix(FILE *inner, const char *pfx, unsigned int flags)
 *  returns a FILE *.  Output written to this FILE * has each line
 *  prefixed with pfx and is then sent to inner.
 *
 * The pfx string must remain valid for the life of the stream.
 *
 * If flags has FWPF_CLOSE set, closing the wrapper stream closes the
 *  inner stream as well; otherwise, nothing in particular happens when
 *  the wrapper stream is closed.
 *
 * Errors when writing output to the inner stream are ignored.
 */
extern FILE *fwrap_prefix(FILE *, const char *, unsigned int);
#define FWPF_CLOSE 0x00000001

/*
 * fopen_alloc
 *
 * fopen_alloc(char **sp, int *lp) returns a FILE *.  Writes to this
 *  FILE * are accumulated.  When the stream is closed, *sp is set to
 *  point to the accumulated string and *lp is set to its length.  One
 *  NUL is always appended; it is not counted in the length.
 *
 * If either pointer is nil, that datum is not returned.
 */
extern FILE *fopen_alloc(char **, int *);

#endif