/*
 * Program:	Operating-system dependent routines -- System V R3 version
 *
 *  WARNING - this file is yet incomplete and untested!
 *
 * Author:	Mark Crispin
 *		Networks and Distributed Computing
 *		Computing & Communications
 *		University of Washington
 *		Administration Building, AG-44
 *		Seattle, WA  98195
 *		Internet: MRC@CAC.Washington.EDU
 *
 * Date:	1 August 1988
 * Last Edited:	7 January 1992
 *
 * Sponsorship:	The original version of this work was developed in the
 *		Symbolic Systems Resources Group of the Knowledge Systems
 *		Laboratory at Stanford University in 1987-88, and was funded
 *		by the Biomedical Research Technology Program of the National
 *		Institutes of Health under grant number RR-00785.
 *
 * Original version Copyright 1988 by The Leland Stanford Junior University.
 * Copyright 1992 by the University of Washington.
 *
 *  Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose and without fee is hereby granted, provided
 * that the above copyright notices appear in all copies and that both the
 * above copyright notices and this permission notice appear in supporting
 * documentation, and that the name of the University of Washington or The
 * Leland Stanford Junior University not be used in advertising or publicity
 * pertaining to distribution of the software without specific, written prior
 * permission.  This software is made available "as is", and
 * THE UNIVERSITY OF WASHINGTON AND THE LELAND STANFORD JUNIOR UNIVERSITY
 * DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, WITH REGARD TO THIS SOFTWARE,
 * INCLUDING WITHOUT LIMITATION ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE, AND IN NO EVENT SHALL THE UNIVERSITY OF
 * WASHINGTON OR THE LELAND STANFORD JUNIOR UNIVERSITY BE LIABLE FOR ANY
 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
 * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
 * CONTRACT, TORT (INCLUDING NEGLIGENCE) OR STRICT LIABILITY, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

/* TCP input buffer */

#define BUFLEN 8192


/* TCP I/O stream (must be before osdep.h is included) */

#define TCPSTREAM struct tcp_stream
TCPSTREAM {
  char *host;			/* host name */
  char *localhost;		/* local host name */
  int tcpsi;			/* input socket */
  int tcpso;			/* output socket */
  int ictr;			/* input counter */
  char *iptr;			/* input pointer */
  char ibuf[BUFLEN];		/* input buffer */
};


#include <stdio.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <string.h>
#include <ctype.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <ctype.h>
#include <errno.h>
extern int errno;		/* just in case */
#include <pwd.h>
#include <syslog.h>
#include "osdep.h"
#include "mail.h"
#include "misc.h"

extern int sys_nerr;
extern char *sys_errlist[];

#define toint(c)	((c)-'0')
#define isodigit(c)	(((unsigned)(c)>=060)&((unsigned)(c)<=067))

/* Write current time in RFC 822 format
 * Accepts: destination string
 */

char *days[] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
char *months[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};

void rfc822_date (date)
	char *date;
{
  int zone;
  char *zonename;
  struct tm *t;
  struct timeval tv;
  struct timezone tz;
  gettimeofday (&tv,&tz);	/* get time and timezone poop */
  t = localtime (&tv.tv_sec);	/* convert to individual items */
				/* use this for older systems */
  zone = (t->tm_isdst ? 60 : 0) -tz.tz_minuteswest;
  zonename = tzname[t->tm_isdst != 0];
				/* and output it */
  sprintf (date,"%s, %d %s %d %02d:%02d:%02d %+03d%02d (%s)",
	   days[t->tm_wday],t->tm_mday,months[t->tm_mon],t->tm_year+1900,
	   t->tm_hour,t->tm_min,t->tm_sec,zone/60,abs (zone) % 60,zonename);
}

/* Get a block of free storage
 * Accepts: size of desired block
 * Returns: free storage block
 */

void *fs_get (size)
	size_t size;
{
  void *block = malloc (size);
  if (!block) fatal ("Out of free storage");
  return (block);
}


/* Resize a block of free storage
 * Accepts: ** pointer to current block
 *	    new size
 */

void fs_resize (block,size)
	void **block;
	size_t size;
{
  if (!(*block = realloc (*block,size))) fatal ("Can't resize free storage");
}


/* Return a block of free storage
 * Accepts: ** pointer to free storage block
 */

void fs_give (block)
	void **block;
{
  free (*block);
  *block = NIL;
}


/* Report a fatal error
 * Accepts: string to output
 */

void fatal (string)
	char *string;
{
  mm_fatal (string);		/* output the string */
  syslog (LOG_ALERT,"IMAP C-Client crash: %s",string);
  abort ();			/* die horribly */
}

/* Copy string with CRLF newlines
 * Accepts: destination string
 *	    pointer to size of destination string
 *	    source string
 *	    length of source string
 */

char *strcrlfcpy (dst,dstl,src,srcl)
	char **dst;
	unsigned long *dstl;
	char *src;
	unsigned long srcl;
{
  long i,j;
  char *d = src;
				/* count number of LF's in source string(s) */
  for (i = srcl,j = 0; j < srcl; j++) if (*d++ == '\012') i++;
				/* resize if not enough space */
  if (i > *dstl) fs_resize ((void **) dst,(*dstl = i) + 1);
  d = *dst;			/* destination string */
				/* copy strings, inserting CR's before LF's */
  while (srcl--) switch (*src) {
  case '\015':			/* unlikely carriage return */
    *d++ = *src++;		/* copy it and any succeeding linefeed */
    if (srcl && *src == '\012') {
      *d++ = *src++;
      srcl--;
    }
    break;
  case '\012':			/* line feed? */
    *d++ ='\015';		/* yes, prepend a CR, drop into default case */
  default:			/* ordinary chararacter */
    *d++ = *src++;		/* just copy character */
    break;
  }
  *d = '\0';			/* tie off destination */
  return *dst;			/* return destination */
}


/* Length of string after strcrlflen applied
 * Accepts: source string
 *	    length of source string
 */

unsigned long strcrlflen (src,srcl)
	char *src;
	unsigned long srcl;
{
  long i = srcl;		/* look for LF's */
  while (srcl--) switch (*src++) {
  case '\015':			/* unlikely carriage return */
    if (srcl && *src == '\012') { src++; srcl--; }
    break;
  case '\012':			/* line feed? */
    i++;
  default:			/* ordinary chararacter */
    break;
  }
  return i;
}

/* Server log in
 * Accepts: user name string
 *	    password string
 *	    optional place to return home directory
 * Returns: T if password validated, NIL otherwise
 */

int server_login (user,pass,home)
	char *user;
	char *pass;
	char **home;
{
  struct passwd *pw = getpwnam (lcase (user));
				/* no entry for this user or root */
  if (!(pw && pw->pw_uid)) return NIL;
				/* validate password */
  if (strcmp (pw->pw_passwd,(char *) crypt (pass,pw->pw_passwd))) return NIL;
  setgid (pw->pw_gid);		/* all OK, login in as that user */
  setuid (pw->pw_uid);
				/* note home directory */
  if (home) *home = cpystr (pw->pw_dir);
  return T;
}

/* TCP/IP open
 * Accepts: host name
 *	    contact port number
 * Returns: TCP/IP stream if success else NIL
 */

TCPSTREAM *tcp_open (host,port)
	char *host;
	int port;
{
  TCPSTREAM *stream = NIL;
  int sock;
  char *s;
  struct sockaddr_in sin;
  struct hostent *host_name;
  char hostname[MAILTMPLEN];
  char tmp[MAILTMPLEN];
  /* The domain literal form is used (rather than simply the dotted decimal
     as with other Unix programs) because it has to be a valid "host name"
     in mailsystem terminology. */
				/* look like domain literal? */
  if (host[0] == '[' && host[(strlen (host))-1] == ']') {
    strcpy (hostname,host+1);	/* yes, copy number part */
    hostname[(strlen (hostname))-1] = '\0';
    if ((sin.sin_addr.s_addr = inet_addr (hostname)) != -1) {
      sin.sin_family = AF_INET;	/* family is always Internet */
      strcpy (hostname,host);	/* hostname is user's argument */
    }
    else {
      sprintf (tmp,"Bad format domain-literal: %s",host);
      mm_log (tmp,ERROR);
      return NIL;
    }
  }

  else {			/* lookup host name, note that brain-dead Unix
				   requires lowercase! */
    strcpy (hostname,host);	/* in case host is in write-protected memory */
    if ((host_name = gethostbyname (lcase (hostname)))) {
				/* copy address type */
      sin.sin_family = host_name->h_addrtype;
				/* copy host name */
      strcpy (hostname,host_name->h_name);
				/* copy host addresses */
      memcpy (&sin.sin_addr,host_name->h_addr,host_name->h_length);
    }
    else {
      sprintf (tmp,"No such host as %s",host);
      mm_log (tmp,ERROR);
      return NIL;
    }
  }

				/* copy port number in network format */
  if (!(sin.sin_port = htons (port))) fatal ("Bad port argument to tcp_open");
				/* get a TCP stream */
  if ((sock = socket (sin.sin_family,SOCK_STREAM,0)) < 0) {
    sprintf (tmp,"Unable to create TCP socket: %s",strerror (errno));
    mm_log (tmp,ERROR);
    return NIL;
  }
				/* open connection */
  if (connect (sock,(struct sockaddr *)&sin,sizeof (sin)) < 0) {
    sprintf (tmp,"Can't connect to %s,%d: %s",hostname,port,strerror (errno));
    mm_log (tmp,ERROR);
    return NIL;
  }
				/* create TCP/IP stream */
  stream = (TCPSTREAM *) fs_get (sizeof (TCPSTREAM));
				/* copy official host name */
  stream->host = cpystr (hostname);
				/* get local name */
  gethostname (tmp,MAILTMPLEN-1);
  stream->localhost = cpystr ((host_name = gethostbyname (tmp)) ?
			      host_name->h_name : tmp);
				/* init sockets */
  stream->tcpsi = stream->tcpso = sock;
  stream->ictr = 0;		/* init input counter */
  return stream;		/* return success */
}

/* TCP/IP authenticated open
 * Accepts: host name
 *	    service name
 * Returns: TCP/IP stream if success else NIL
 */

TCPSTREAM *tcp_aopen (host,service)
	char *host;
	char *service;
{
  TCPSTREAM *stream = NIL;
  struct hostent *host_name;
  char hostname[MAILTMPLEN];
  int i;
  int pipei[2],pipeo[2];
  /* The domain literal form is used (rather than simply the dotted decimal
     as with other Unix programs) because it has to be a valid "host name"
     in mailsystem terminology. */
				/* look like domain literal? */
  if (host[0] == '[' && host[i = (strlen (host))-1] == ']') {
    strcpy (hostname,host+1);	/* yes, copy without brackets */
    hostname[i-1] = '\0';
  }
				/* note that Unix requires lowercase! */
  else if (host_name = gethostbyname (lcase (strcpy (hostname,host))))
    strcpy (hostname,host_name->h_name);
				/* make command pipes */
  if (pipe (pipei) < 0) return NIL;
  if (pipe (pipeo) < 0) {
    close (pipei[0]); close (pipei[1]);
    return NIL;
  }
  if ((i = fork ()) < 0) {	/* make inferior process */
    close (pipei[0]); close (pipei[1]);
    close (pipeo[0]); close (pipeo[1]);
    return NIL;
  }
  if (i) {			/* parent? */
    close (pipei[1]);		/* close child's side of the pipes */
    close (pipeo[0]);
  }
  else {			/* child */
    dup2 (pipei[1],1);		/* parent's input is my output */
    dup2 (pipei[1],2);		/* parent's input is my error output too */
    close (pipei[0]); close (pipei[1]);
    dup2 (pipeo[0],0);		/* parent's output is my input */
    close (pipeo[0]); close (pipeo[1]);
				/* now run it */
    execl ("/usr/ucb/rsh","rsh",hostname,"exec",service,0);
    _exit (1);			/* spazzed */
  }

				/* create TCP/IP stream */
  stream = (TCPSTREAM *) fs_get (sizeof (TCPSTREAM));
				/* copy official host name */
  stream->host = cpystr (hostname);
				/* get local name */
  gethostname (hostname,MAILTMPLEN-1);
  stream->localhost = cpystr ((host_name = gethostbyname (hostname)) ?
			      host_name->h_name : hostname);
  stream->tcpsi = pipei[0];	/* init sockets */
  stream->tcpso = pipeo[1];
  stream->ictr = 0;		/* init input counter */
  return stream;		/* return success */
}

/* TCP/IP receive line
 * Accepts: TCP/IP stream
 * Returns: text line string or NIL if failure
 */

char *tcp_getline (stream)
	TCPSTREAM *stream;
{
  int n,m;
  char *st;
  char *ret;
  char *stp;
  char tmp[2];
  fd_set fds;
  FD_ZERO (&fds);		/* initialize selection vector */
  if (stream->tcpsi < 0) return NIL;
  while (stream->ictr < 1) {	/* if nothing in the buffer */
    FD_SET (stream->tcpsi,&fds);/* set bit in selection vector */
				/* block and read */
    if ((select (stream->tcpsi+1,&fds,0,0,0) < 0) ||
	((stream->ictr = read (stream->tcpsi,stream->ibuf,BUFLEN)) < 1)) {
      close (stream->tcpsi);	/* nuke the socket */
      if (stream->tcpsi != stream->tcpso) close (stream->tcpso);
      stream->tcpsi = stream->tcpso = -1;
      return NIL;
    }
    stream->iptr = stream->ibuf;/* point at TCP buffer */
  }
  st = stream->iptr;		/* save start of string */
  n = 0;			/* init string count */
  while (stream->ictr--) {	/* look for end of line */
				/* saw the trailing CR? */
    if (stream->iptr++[0] == '\015') {
      ret = (char *) fs_get (n+1);
      memcpy (ret,st,n);	/* copy into a free storage string */
      ret[n] = '\0';		/* tie off string with null */
				/* eat the line feed */
      tcp_getbuffer (stream,1,tmp);
      return ret;		/* return it to caller */
    }
    ++n;			/* else count and try next character */
  }
  stp = (char *) fs_get (n);	/* copy first part of string */
  memcpy (stp,st,n);
				/* recurse to get remainder */
  if (st = tcp_getline (stream)) {
				/* build total string */
    ret = (char *) fs_get (n+1+(m = strlen (st)));
    memcpy (ret,stp,n);		/* copy first part */
    memcpy (ret+n,st,m);	/* and second part */
    ret[n+m] = '\0';		/* tie off string with null */
    fs_give ((void **) &st);	/* flush partial string */
    fs_give ((void **) &stp);	/* flush initial fragment */
  }
  else ret = stp;		/* return the fragment */
  return ret;
}

/* TCP/IP receive buffer
 * Accepts: TCP/IP stream
 *	    size in bytes
 *	    buffer to read into
 * Returns: T if success, NIL otherwise
 */

int tcp_getbuffer (stream,size,buffer)
	TCPSTREAM *stream;
	unsigned long size;
	char *buffer;
{
  unsigned long n;
  char *bufptr = buffer;
  fd_set fds;
  FD_ZERO (&fds);		/* initialize selection vector */
  if (stream->tcpsi < 0) return NIL;
  while (size > 0) {		/* until request satisfied */
    while (stream->ictr < 1) {	/* if nothing in the buffer */
      FD_SET (stream->tcpsi,&fds);
				/* block and read */
      if ((select (stream->tcpsi+1,&fds,0,0,0) < 0) ||
	  ((stream->ictr = read (stream->tcpsi,stream->ibuf,BUFLEN)) < 1)) {
	close (stream->tcpsi);	/* nuke the socket */
	if (stream->tcpsi != stream->tcpso) close (stream->tcpso);
	stream->tcpsi = stream->tcpso = -1;
	return NIL;
      }
				/* point at TCP buffer */
      stream->iptr = stream->ibuf;
    }
    n = min (size,stream->ictr);/* number of bytes to transfer */
				/* do the copy */
    memcpy (bufptr,stream->iptr,n);
    bufptr += n;		/* update pointer */
    stream->iptr +=n;
    size -= n;			/* update # of bytes to do */
    stream->ictr -=n;
  }
  bufptr[0] = '\0';		/* tie off string */
  return T;
}

/* TCP/IP send string as record
 * Accepts: TCP/IP stream
 * Returns: T if success else NIL
 */

int tcp_soutr (stream,string)
	TCPSTREAM *stream;
	char *string;
{
  int i;
  unsigned long size = strlen (string);
  fd_set fds;
  FD_ZERO (&fds);		/* initialize selection vector */
  if (stream->tcpso < 0) return NIL;
  while (size > 0) {		/* until request satisfied */
    FD_SET (stream->tcpso,&fds);/* set bit in selection vector */
    if ((select (stream->tcpso+1,0,&fds,0,0) < 0) ||
	((i = write (stream->tcpso,string,size)) < 0)) {
      puts (strerror (errno));
      close (stream->tcpsi);	/* nuke the socket */
      if (stream->tcpsi != stream->tcpso) close (stream->tcpso);
      stream->tcpsi = stream->tcpso = -1;
      return NIL;
    }
    size -= i;			/* count this size */
    string += i;
  }
  return T;			/* all done */
}


/* TCP/IP close
 * Accepts: TCP/IP stream
 */

void tcp_close (stream)
	TCPSTREAM *stream;
{

  if (stream->tcpsi >= 0) {	/* no-op if no socket */
    close (stream->tcpsi);	/* nuke the socket */
    if (stream->tcpsi != stream->tcpso) close (stream->tcpso);
    stream->tcpsi = stream->tcpso = -1;
  }
				/* flush host names */
  fs_give ((void **) &stream->host);
  fs_give ((void **) &stream->localhost);
  fs_give ((void **) &stream);	/* flush the stream */
}

/* TCP/IP get host name
 * Accepts: TCP/IP stream
 * Returns: host name for this stream
 */

char *tcp_host (stream)
	TCPSTREAM *stream;
{
  return stream->host;		/* return host name */
}


/* TCP/IP get local host name
 * Accepts: TCP/IP stream
 * Returns: local host name
 */

char *tcp_localhost (stream)
	TCPSTREAM *stream;
{
  return stream->localhost;	/* return local host name */
}

/* Emulator for BSD gethostid() call
 * Returns: unique identifier for this machine
 */

long gethostid ()
{
  struct sockaddr_in sin;
  int inet = t_open (TLI_TCP, O_RDWR, 0);
  if (inet < 0) return 0;
  getmyinaddr (inet,&sin,sizeof (sin));
  close (inet);
  return sin.sin_addr.s_addr;
}


/* Emulator for BSD random() call
 * Returns: long random number
 */

long random ()
{
  static int beenhere = 0;
  if (!beenhere) {
    beenhere = 1;
    srand48 (getpid ());
  }
  return lrand48 ();
}


/* Copy memory block
 * Accepts: destination pointer
 *	    source pointer
 *	    length
 * Returns: destination pointer
 */

void *memmove (s,ct,n)
	void *s;
	void *ct;
	int n;
{
  char *dp, *sp;
  int i;
  unsigned long dest = (unsigned long) s;
  unsigned long src = (unsigned long) ct;
  if (((dest < src) && ((dest + n) < src)) ||
      ((dest > src) && ((src + n) < dest))) return memcpy (s, ct, n);
  dp = s;
  sp = ct;
  if (dest < src) for (i = 0; i < n; ++i) dp[i] = sp[i];
  else if (dest > src) for (i = n - 1; i >= 0; --i) dp[i] = sp[i];
  return s;
}

/* Emulator for BSD re_comp() call
 * Accepts: character string to compile
 * Returns: 0 if successful, else error message
 * Uses the regexpr(3X) libraries.
 * Don't forget to link against /usr/lib/libgen.a
 */

#define PATMAX 256
static char re_space[PATMAX];

char *re_comp (str)
	char *str;
{
  char *c;
  static char *invalstr = "invalid string";
  if (str) {			/* must have a string to compile */
    c = compile (str,re_space,re_space + PATMAX);
    if ((c >= re_space) && (c <= re_space + PATMAX)) return 0;
  }
  re_space[0] = 0;
  return invalstr;
}


/* Emulator for BSD re_exec() call
 * Accepts: string to match
 * Returns: 1 if string matches, 0 if fails to match, -1 if re_comp() failed
 */

long re_exec (str)
	char *str;
{
  if (!re_space[0]) return -1;	/* re_comp() failed? */
  return step (str,re_space) ? 1 : 0;
}

/* Emulator for BSD scandir() call
 * Accepts: directory name
 *	    destination pointer of names array
 *	    selection function
 *	    comparison function
 * Returns: number of elements in the array or -1 if error
 */

#define DIRSIZ(d) d->d_reclen

int scandir (dirname,namelist,select,compar)
	char *dirname;
	struct dirent ***namelist;
	int (*select) ();
	int (*compar) ();
{
  struct dirent *p,*d,**names;
  int nitems;
  struct stat stb;
  long nlmax;
  DIR *dirp = opendir (dirname);/* open directory and get status poop */
  if ((!dirp) || (fstat (dirp->dd_fd,&stb) < 0)) return -1;
  nlmax = stb.st_size / 24;	/* guesstimate at number of files */
  names = (struct dirent **) fs_get (nlmax * sizeof (struct dirent *));
  nitems = 0;			/* initially none found */
  while (d = readdir (dirp)) {	/* read directory item */
				/* matches select criterion? */
    if (select && !(*select) (d)) continue;
				/* get size of dirent record for this file */
    p = (struct dirent *) fs_get (DIRSIZ (d));
    p->d_ino = d->d_ino;	/* copy the poop */
    p->d_off = d->d_off;
    p->d_reclen = d->d_reclen;
    strcpy (d->d_name,p->d_name);
    if (++nitems >= nlmax) {	/* if out of space, try bigger guesstimate */
      nlmax *= 2;		/* double it */
      fs_resize ((void **) names,nlmax * sizeof (struct dirent *));
    }
    names[nitems - 1] = p;	/* store this file there */
  }
  closedir (dirp);		/* done with directory */
				/* sort if necessary */
  if (nitems && compar) qsort (names,nitems,sizeof (struct dirent *),compar);
  *namelist = names;		/* return directory */
  return nitems;		/* and size */
}

/* Emulator for BSD flock() call
 * Accepts: file descriptor
 *	    operation bitmask
 * Returns: 0 if successful, -1 if failure
 * Note: this emulator does not handle shared locks
 */

int flock (fd, operation)
	int fd;
	int operation;
{
  int func;
				/* translate to flock() operation */
  if (operation & LOCK_UN) func = F_ULOCK;
  else if (operation & (LOCK_EX|LOCK_SH))
    func = (operation & LOCK_NB) ? F_TLOCK : F_LOCK;
  else {
    errno = EINVAL;
    return -1;
  }
  return lockf (fd,func,0);	/* do the lockf() */
}


/* Emulator for BSD gettimeofday() call
 * Accepts: address where to write timeval information
 *	    address where to write timezone information
 * Returns: 0 if successful, -1 if failure
 */

int gettimeofday (tp,tzp)
	struct timeval *tp;
	struct timezone *tzp;
{
  tp->tv_sec = time (0);	/* time since 1-Jan-70 00:00:00 GMT in secs */
				/* others aren't used in current code */
  if (tzp) tzp->tz_minuteswest = tzp->tz_dsttime = 0;
  tp->tv_usec = 0;
  return 0;
}

/* Emulator for BSD utimes() call
 * Accepts: file name
 *	    timeval vector for access and updated time
 * Returns: 0 if successful, -1 if failure
 */

int utimes (file,tvp)
	char *file;
	struct timeval tvp[2];
{
  struct utimbuf tb;
  tb.actime = tvp[0].tv_sec;	/* accessed time */
  tb.modtime = tvp[1].tv_sec;	/* updated time */
  return utime (file,&tb);
}



#ifdef	flock		/* undef this for now */
#undef	flock
#endif

ftruncate(f, l)
int	f;
long	l;
{
	struct	flock fl;

	fl.l_whence = 0;
	fl.l_len = 0;
	fl.l_start = l;
	fl.l_type = F_WRLCK;

	return(fcntl(f, F_FREESP, &fl));
}

