fchdir (BPX1FCD, BPX4FCD) — Change the working directory
Function
The fchdir service changes your working directory from the current one to a new one. The working directory is the starting point for path searches of path names not beginning with a slash.
For corresponding service using a path name, see chdir (BPX1CHD, BPX4CHD) — Change the working directory.
Requirements
| Operation | Environment |
|---|---|
| Authorization: | Supervisor state or problem state, any PSW key |
| Dispatchable unit mode: | Task |
| Cross memory mode: | PASN = HASN |
| AMODE (BPX1FCD): | 31-bit |
| AMODE (BPX4FCD): | 64-bit |
| ASC mode: | Primary mode |
| Interrupt status: | Enabled for interrupts |
| Locks: | Unlocked |
| Control parameters: | All parameters must be addressable by the caller and in the primary address space. |
Format
CALL BPX1FCD,(Directory_file_descriptor,
Return_value,
Return_code,
Reason_code)AMODE 64 callers use BPX4FCD with the same parameters.
Parameters
- Directory_file_descriptor
- Supplied parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword containing the directory file descriptor that was returned when the directory was opened (see opendir (BPX1OPD, BPX4OPD) — Open a directory), which is to become the new working directory. It can also be specified as the name of a fullword containing the file descriptor of an open directory (see open (BPX1OPN, BPX4OPN) — Open a file).
- Return_value
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword where the fchdir service returns
0if the request is successful, or -1if it is not successful. - Return_code
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword in which the fchdir service stores the return code. The fchdir service returns Return_code only if Return_value is-1. For a list of return code values, see Return codes (errnos) in z/OS UNIX System Services Messages and Codes.The fchdir service can return one of the following values in the Return_code parameter:Return_code Explanation EACCES The calling process does not have search permission for the directory referenced by the file descriptor. EBADF The file descriptor parameter is not a valid file descriptor. ENOTDIR The open file descriptor does not refer to a directory. The following reason code can accompany the return code: JRChdNotDir. EINTR A signal was caught during the execution of fchdir(). EIO An I/O error occurred while reading from or writing to the file system. The following reason codes can accompany the return code: JRQuiescing. - Reason_code
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword where the fchdir service stores the reason code. The fchdir service returns a Reason_code only if Return_value is
-1. Reason_code further qualifies the Return_code value. For a list of reason codes, see Reason codes in z/OS UNIX System Services Messages and Codes.
Related services
- chdir (BPX1CHD, BPX4CHD) — Change the working directory
- closedir (BPX1CLD, BPX4CLD) — Close a directory
- getcwd (BPX1GCW, BPX4GCW) — Get the path name of the working directory
- mkdir (BPX1MKD, BPX4MKD) — Make a directory
- opendir (BPX1OPD, BPX4OPD) — Open a directory
- readdir (BPX1RDD, BPX4RDD) — Read an entry from a directory
- rmdir (BPX1RMD, BPX4RMD) — Remove a directory
- unlink (BPX1UNL, BPX4UNL) — Remove a directory entry
Characteristics and restrictions
There are no restrictions on the use of the fchdir service.