File

classes
   aopen          gets           scanvar        wopen          
   chooser        isopen         seek           xopen          
   close          printf         tell           
   eof            ropen          vread          
   getname        scanstr        vwrite         

SYNTAX

fobj = new File()
fobj = new File("filename")

DESCRIPTION

This class allows you to open several files at once, whereas the top level functions, ropen and wopen , allow you to deal only with one file at a time.

The functionality of xopen is not implemented in this class so use that execute a sequence of interpreter commands in a file.

EXAMPLES

objref f1, f2, f3	//declare object references
f1 = new File()		//state that f1, f2, and f3 are pointers to the File class
f2 = new File()
f3 = new File()
f1.ropen("file1")	//open file1 for reading
f2.wopen("file2")	//open file2 for writing
f3.aopen("file3")	//open file3 for appending to the end of the file
opens file1, file2, and file3 for reading, writing, and appending (respectively).

BUGS

The mswindows/dos version must deal with the difference between binary and text mode files. The difference is transparent to the user except for one limitation. If you mix text and binary data and you write text first to the file, then you need to do a File.seek(0) to explicitly switch to binary mode just after opening the file and prior to the first File.printf. An error message will occur if you read/write text to a file in text mode and then try to read/write a binary vector. This issue does not arise with the unix version.

SEE ALSO

IO , ropen , xopen , wopen


ropen

File

SYNTAX

.ropen()
.ropen("name")

DESCRIPTION

Open the file for reading. If the argument is not present it opens (for reading) the last specified file.


wopen

File

SYNTAX

.wopen()
.wopen("name")

DESCRIPTION

Open the file for writing. If the argument is not present it opens the last specified file.


aopen

File

SYNTAX

.aopen()
.aopen("name")

DESCRIPTION

Open the file for appending to the end of the file. If the argument is not present it opens the last specified file.


xopen

File

SYNTAX

.xopen()
.xopen("name")

DESCRIPTION

Open the file and execute it. (not implemented)

Note: if instead of a "name", the number 0,1,or 2 is specified then the stdin, stdout, or stderr is opened. (not implemented)


close

File

SYNTAX

.close()

DESCRIPTION

Flush and close the file. This occurs automatically whenever opening another file or destroying the object.


printf

File

SYNTAX

.printf("format", args, ...)

DESCRIPTION

As in standard C printf and the normal hoc printf .


scanvar

File

SYNTAX

.scanvar()

DESCRIPTION

Reads the next number as in the hoc function fscan() and returns its value.

Note: in order that .eof will return true after the last number, the last digit of that number should either be the last character in the file or be followed by a newline which is the last character in the file.


scanstr

File

SYNTAX

.scanstr(strdef)

DESCRIPTION

Read the next string (delimited by whitespace) into strdef. Returns the length of a string (if failure then returns -1 and strdef is unchanged).


gets

File

SYNTAX

.gets(strdef)

DESCRIPTION

Read up to and including end of line. Returns length of string.


getname

File

SYNTAX

.getname(strdef)

DESCRIPTION

Return the name of the last specified file in strdef.


eof

File

SYNTAX

.eof()

DESCRIPTION

Return true if at end of ropen'd file.


isopen

File

SYNTAX

.isopen()

DESCRIPTION

Return true if a file is open.


chooser

File

SYNTAX

.chooser()
.chooser("w,r,a,x or nothing")
.chooser("w,r,a,x or nothing", "Banner", "filter", "accept", "cancel", "path")

DESCRIPTION

File chooser interface for writing , reading, appending, or just specifying a filename without opening. The banner is optional. The filter, eg. "*.dat" specifies the files shown in the browser part of the chooser. The "path" arg specifies the file or directory to use when the browser first pops up. The form with args sets the style of the chooser but does not pop it up. With no args, the browser pops up and can be called several times. Each time starting where it left off previously. The "x" style is unimplemented. Use
		f.chooser("", "Execute a hoc file", "*.hoc", "Execute")
		if (f.chooser()) {
			f.getname(str)
			xopen(str)
		}
The following comes courtesy of Zach Mainen, zach@helmholtz.sdsc.edu.


vwrite

File

SYNTAX

.vwrite(&x)
.vwrite(&x, i)
.vwrite(n, &x)
.vwrite(n, &x, i)

DESCRIPTION

Write binary doubles to a file from an array or variable using fwrite(). The form with two arguments specifies the number of elements to write and the address from which to begin writing. With one argument, n is assumed to be 1. Must be careful that the length of x[] is at least i+n.


vread

File

SYNTAX

.vread(&x)
.vread(&x, i)
.vread(n, &x)
.vread(n, &x, i)

DESCRIPTION

Read binary doubles from a file into a pre-existing array or variable using fread().

SEE ALSO

vwrite


seek

File

SYNTAX

.seek()
.seek(offset)
.seek(offset,origin)

DESCRIPTION

Set the file position. Any subsequent file access will access data beginning at the new position. Without arguments, goes to the beginning of file. Offset is in characters and is measured from the beginning of the file unless origin is 1 (measures from the current position) or 2 (from the end of the file). Returns 0 if successful, non-zero on error. Used with .tell().


tell

File

SYNTAX

.tell()

DESCRIPTION

Return the current file position or -1 on error. Used with .seek().


neuron/general/classes/file.hel : Dec 19 1996