| Files | 1!: |
| 1!:0 y |
Directory. y is a string of the path
search expression (a boxed string is also accepted);
the result is a 5-column table of the file name,
modification time, size, permission, and attributes,
individually boxed. For example, try 1!:0 '*.*'.
The permission and attribute columns are system dependent.
For example, in Windows:1!:0 'j.exe' +-----+-----------------+------+---+------+ |j.exe|1998 2 2 14 33 46|676864|rwx|-----a| +-----+-----------------+------+---+------+Permission is a 3-letter string indicating the read, write, and execute permissions. Attributes is a 6-letter string indicating read-only, hidden, system, volume label, directory, and archive. |
| 1!:1 y |
Read. y is a file name or a file number
(produced by 1!:21); the result is a string of the file contents.,
e.g. 1!:1 <'abc.q'. The following values
for y are also permitted: 1 read from the keyboard 3 (Unix only) read from standard input (stdin) |
| x 1!:2 y |
Write. x is a string of the new contents
of the file; y is a file name or file number
(produced by 1!:21). The following values
for y are also permitted: 2 screen output. 4 (Unix only) standard output (stdout) 5 (Unix only) standard error (stderr) |
| x 1!:3 y | Append. Like x 1!:2 y, but appends rather than replaces |
| 1!:4 y | Size |
| 1!:5 y | Create Directory. y is a (boxed) directory name |
| [x] 1!:6 y | Query/Set Attributes. |
| [x] 1!:7 y | Query/Set Permissions. |
| 1!:11 y |
Indexed Read. y is a list of a boxed file name
(or number) and a boxed index and length. The index may be negative.
If the length is elided, the read goes to the end. For example:1!:11 'abc.x';1000 20 f=: 1!:21 <'abc.x' 1!:11 f,1000 20 |
| x 1!:12 y | Indexed Write. Like indexed read; x specifies the string to be written |
| 1!:20 y | File Numbers and Names. A 2-column table of the open file numbers and names |
| 1!:21 y | Open. Open file named y, creating it if necessary; result is a file number. |
| 1!:22 y | Close. Close file named or numbered y. Any locks are released. |
| 1!:30 y | Locks. A 3-column integer table of the file number, index, and length of file locks. The argument y is required but ignored. |
| 1!:31 y | Lock. y is a 3-element integer vector of the file number, index, and length of the file region to be locked; the result is 1 if the request succeeded, and 0 if it did not. |
| 1!:32 y | Unlock. y is a 3-element integer vector of the file number, index, and length of the file region to be unlocked. |
| 1!:40 y | Path. The directory path of the J application executable file. |
| 1!:41 y | Server Path. The directory path of the JDLLServer j.dll file (or '' if not JDLLServer). |
| 1!:42 y | Library Path. The directory path of the directory where the J scripts are located. |
| 1!:55 y | Erase File/Directory. e.g., 1!:55<'careful' |