Open command expressions : Open file « File « Perl






  1. Perl
  2. File
  3. Open file

Open command expressions

    

EXPRESSION                       EFFECT

open (FH, "<filename")           Opens file name for reading.

open (FH, "+<filename")          Opens file name for both reading and writing.

open (FH, ">filename")           Opens file name for writing.

open (FH, "+>filename")          Opens file name for both reading and writing.

open (FH, ">>filename")          Opens file name for appending.

open (FH, "command|")            Runs the command and pipes its output to the filehandle.

open (FH, "|command")            Pipes the output along the filehandle to the command.

open (FH, "-")                   Opens STDIN.

open (FH, ">-")                  Opens STDOUT.

open (FH, "<&=N")                Where N is a number, this performs the equivalent of C's fdopen for reading.

open (FH, ">&=N")                Where N is a number, this performs the equivalent of C's fdopen for writing.








Related examples in the same category

1.To open a file for appending:
2.To open a file for reading and writing:
3.To open a file for reading:
4.To open a file for writing
5.open (FILEHANDLE, "<&FILEHANDLE2");
6.open (FILEHANDLE2, "<&=FILEHANDLE");
7.open(MYFILE, ">>c:\\outfile.dat")
8.Open FILEHANDLE
9.Open Operators
10.Open a file
11.Open a file from another file handle
12.Open a file to read
13.Open a pipe to the who command
14.Open file for update
15.Open file for writing
16.Open file reading
17.Open for Appending
18.Open for Reading
19.Open for Reading and Writing
20.Open for Writing
21.Open for writing first, then reading
22.Opening an input filter on a Win32 platform
23.Opening files and using file handles: open(filehandle, name);
24.Opens two files and copies one into another.
25.Checks whether an unopened file actually exists.
26.Input Filter: open(FILEHANDLE, COMMAND|);
27.Sending the Output of a Filter to a File: open(STDOUT, ">/dev/tty");
28.Uses die when testing for a successful file open operation.
29.Using open to connect different processes