Ticket #187: cwd.note

Issue: Cwd->abs_path('F:testpl.cmd') generates the message
  sys_is_absolute2 = Cwd
  LF
  sys_is_relative2 = Cwd

The string appears in perlE147.dll but I couldn't find an associated source file.

Issue: Cwd->abs_path('F:testpl.cmd') returns F:/ecs/testpl.cmd/Cwd instead of F:/ecs/testpl.cmd

Query: is it legal to do
CD \\server\netname\directoru
for directories on a LAN drive. Should getdcwd support that?

Q:\programs\perl\lib\5.10.0\os2\Cwd.pm
H:\vendors\cpan\PathTools-3.39_01\Cwd.pm
H:\vendors\cpan\PathTools-3.39_01\Cwd.xs
H:\vendors\cpan\PathTools-3.39_01\lib\File\Spec\OS2.pm
H:\vendors\cpan\PathTools-3.39_01\lib\File\Spec\Win32.pm

EMX

char *getcwd (char *buffer, size_t size);

int _getcwd1 (char *buffer, char drive);
Does not check size!

char *_getcwd2 (char *buffer, int size);

char _getdrive (void);

OS/2


Q:\OS2TK45\h\os2.h


Gets the current default drive for the requesting process.


#define INCL_DOSFILEMGR
#include <os2.h>

PULONG    pdisknum;  /*  Address of the number of the default drive. */
PULONG    plogical;  /*  Address of the bit map where the system returns the mapping of the logical drives. */
APIRET    ulrc;      /*  Return Code. */

ulrc = DosQueryCurrentDisk(pdisknum, plogical);

pdisknum (PULONG) - output
Address of the number of the default drive.

The value 1 means drive A, 2 means drive B, 3 means drive C, and so on. The maximum possible value is 26, which corresponds to drive Z.

plogical (PULONG) - output
Address of the bit map where the system returns the mapping of the logical drives.

This bit map is stored in the low-order portion of the 32-bit area.

Logical drives A to Z have one-to-one mapping with bit positions 0 to 25 of the map; for example, bit 0 represents drive A, bit 1 represents drive B, and so on. The settings of these bits indicate which drives exist, as follows:

0The logical drive does not exist.
1The logical drive exists.

ulrc (APIRET) - returns
Return Code.

DosQueryCurrentDisk returns the following value:

0 NO_ERROR

For a full list of error codes, see Errors.

Gets the full path of the current directory for the requesting process on the specified drive.


#define INCL_DOSFILEMGR
#include <os2.h>

ULONG     disknum;  /*  The drive number. */
PBYTE     pBuf;     /*  Address of the full path of the current directory. */
PULONG    pcbBuf;   /*  Address of the length, in bytes, of the pBuf buffer. */
APIRET    ulrc;     /*  Return Code. */

ulrc = DosQueryCurrentDir(disknum, pBuf, pcbBuf);

disknum (ULONG) - input
The drive number.

The value 0 means the current drive, 1 means drive A, 2 means drive B, 3 means drive C, and so on. The maximum possible value is 26, which corresponds to drive Z.

pBuf (PBYTE) - output
Address of the full path of the current directory.

pcbBuf (PULONG) - in/out
Address of the length, in bytes, of the pBuf buffer.


Input This field contains the length, in bytes, of the directory path buffer.

Output If an error is returned because the buffer is too small, this field contains the required length, in bytes, of the buffer.

ulrc (APIRET) - returns
Return Code.

DosQueryCurrentDir returns one of the following values:

0 NO_ERROR
15 ERROR_INVALID_DRIVE
26 ERROR_NOT_DOS_DISK
108 ERROR_DRIVE_LOCKED
111 ERROR_BUFFER_OVERFLOW

For a full list of error codes, see Errors.





For Cwd.pm

sub _os2_cwd {
    my $drive = shift;
    $ENV{'PWD'} = `cmd /c cd $drive\:`;
    chomp $ENV{'PWD'};
    $ENV{'PWD'} =~ s:\\:/:g ;
    return $ENV{'PWD'};
}



For Cwd.xs, assuming EMX

#if defined(OS2)
void
getdcwd(...)
PROTOTYPE: ENABLE
PPCODE:
{
    dXSTARG;
    char drive;
    char *dir;

    /* Drive 0 is the current drive, A-Z are A-Z. */
    if ( items == 0 ||
        (items == 1 && (!SvOK(ST(0)) || (SvPOK(ST(0)) && !SvCUR(ST(0))))))
        drive = 0;
    else if (items == 1 && SvPOK(ST(0)) && SvCUR(ST(0)) &&
             isALPHA(SvPVX(ST(0))[0]))
        drive = SvPVX(ST(0))[0];
    else
        croak("Usage: getdcwd(DRIVE)");

    New(0,dir,MAXPATHLEN,char);
    if (_getcwd1(dir, drive)) {
        sv_setpv_mg(TARG, dir);
        SvPOK_only(TARG);
    }
    else
        sv_setsv(TARG, &PL_sv_undef);

    Safefree(dir);

    XSprePUSH; PUSHs(TARG);
#ifndef INCOMPLETE_TAINTS
    SvTAINTED_on(TARG);
#endif
}

#endif




For Cwd.xs, if not using EMX,

#if defined(OS2)

#define INCL_DOSFILEMGR
#include <os2.h>

void
getdcwd(...)
PROTOTYPE: ENABLE
PPCODE:
{
    dXSTARG;
    ULONG drive;
    PULONG *dir;

    /* Drive 0 is the current drive, 1 is A:, 2 is B:, 3 is C: and so on. */
    if ( items == 0 ||
        (items == 1 && (!SvOK(ST(0)) || (SvPOK(ST(0)) && !SvCUR(ST(0))))))
        drive = 0;
    else if (items == 1 && SvPOK(ST(0)) && SvCUR(ST(0)) &&
             isALPHA(SvPVX(ST(0))[0]))
        drive = toUPPER(SvPVX(ST(0))[0]) - 'A' + 1;
    else
        croak("Usage: getdcwd(DRIVE)");

    New(0,dir,MAXPATHLEN,char);
    if (_getdcwd(drive, dir, MAXPATHLEN)) {
        sv_setpv_mg(TARG, dir);
        SvPOK_only(TARG);
    }
    else
        sv_setsv(TARG, &PL_sv_undef);

    Safefree(dir);

    XSprePUSH; PUSHs(TARG);
    SvTAINTED_on(TARG);
}

#endif