From:	CSBVAX::MRGATE!RELAY-INFO-VAX@CRVAX.SRI.COM@SMTP 12-AUG-1988 02:10
To:	ARISIA::EVERHART
Subj:	Re: VMS versions of rm, mv etc?


Received: From KL.SRI.COM by CRVAX.SRI.COM with TCP; Thu, 11 AUG 88 22:53:51 PDT
Received: from CitHex.Caltech.Edu by KL.SRI.COM with TCP; Thu, 11 Aug 88 22:43:39 PDT
Date:     Thu, 11 Aug 88 22:42:29 PDT
From:     carl@CitHex.Caltech.Edu (Carl J Lydick)
Message-Id: <880811224010.e77@CitHex.Caltech.Edu>
Subject:  Re: VMS versions of rm, mv etc?
In-Reply-To: Your message <1322@ucsfcca.ucsf.edu> dated 10-Aug-1988
To:       cca.ucsf.edu!ccb.ucsf.edu!dick@cgl.ucsf.edu,
         info-vax@CitHex.Caltech.Edu

 > We are using the Gnu gcc compiler to support printing from a VMS
 > MicroVAX II thru the Excelan TCP/IP board to an IBM machine with
 > a big fast printer.  Several parts of the VMS program are rather
 > slow and complicated because we don't know the right way to:

Even though you're using the GNU C compiler, that shouldn't stop you from
using the VAX C Run-Time Library.  Using said library probably won't make
your program any faster, but it could make it less complicated.  The
appropriate calls are listed below.
********************************************************************************
 - remove a file (rm) from within a C program
            int  delete(char *file_specification);
 - rename a file (mv)
            int rename (const char *old_file_spec, const char *new_file_spec);
 - start a process & pass a command line
            int system (const char *string);
 - make a directory (mkdir)
            int  mkdir(char *dir_spec, unsigned mode [,unsigned uic,
                       unsigned max_versions, unsigned r_v_num]);

       The argument, dir_spec, is a valid VAX/VMS or  DEC/Shell  directory
       specification which can include a device name.  The argument, mode,
       sets the file protection (see chmod in The Guide  to  VAX  C);  the
       argument,  uic,  sets  the  User Identification Code; the argument,
       r_v_num sets the relative volume  number.   This  function  returns
       zero on success and -1 on failure.
 - remove a directory (rmdir)
            int chmod(char *name, unsigned mode);
            int  delete(char *file_specification);

	First chmod the directory to give yourself delete permission on it,
	then use delete to delete it.  You can't delete the directory if
	there are any files still in it.
 - change ownership of a file (chown) In Unix compatibility library??
            int chown(char *name, unsigned owner, unsigned group);
 - change permissions of a file (chmod) In same library??
            int chmod(char *name, unsigned mode);
********************************************************************************
 - link a new filename to also refer to an existing file (ln)

This one's a little tougher, since DEC discourages users creating multiple
directory entries for files.  There is, therefore, no corresponding VAX
C Run-Time function.  However, the following program does the job.  You'll
have to come up with your own versions of FAB.H and NAM.H.
********************************************************************************
#include fab.h
#include nam.h
ln(oldname, newname)
char *oldname, *newname;
{   struct FAB fab;
    struct NAM nam;
    char esabuf[64];
    short did[3], fid[3];
    int i, stat;

    fab = cc$rms_fab;
    nam = cc$rms_nam;
    fab.fab$l_fna = oldname;
    fab.fab$b_fns = strlen(oldname);
    fab.fab$b_fac = FAB$M_GET;
    fab.fab$w_ifi = 0;
    fab.fab$b_shr = FAB$M_SHRGET;
    fab.fab$l_nam = &nam;
    stat = SYS$OPEN(&fab);
    if ((stat & 7) != 1)
        exit(stat);
    SYS$CLOSE(&fab);
    for (i = 0; i < 3; ++i)
    {   did[i] = nam.nam$w_did[i];
        fid[i] = nam.nam$w_fid[i];
    }
    fab = cc$rms_fab;
    nam = cc$rms_nam;
    fab.fab$l_fna = newname;
    fab.fab$b_fns = strlen(newname);
    fab.fab$w_ifi = 0;
    fab.fab$l_nam = &nam;
    nam.nam$l_esa = esabuf;
    nam.nam$b_ess = 64;
    stat = SYS$PARSE(&fab);
    if ((stat & 7) != 1)
        exit(stat);
    for (i = 0; i < 3; ++i)
    {   nam.nam$w_did[i] = did[i];
        nam.nam$w_fid[i] = fid[i];
    }
    stat = SYS$ENTER(&fab);
    exit(stat);
}