Error Output Redirect Unix
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is connected to the terminal keyboard and standard output and error to the terminal screen. The way of indicating an end-of-file on the default linux redirect error output standard input, a terminal, is usually
Windows Redirect Error Output
to a file, is accomplished by specifying the destination on the command line using a redirection metacharacter dos redirect error output followed by the desired destination. C Shell Family Some of the forms of redirection for the C shell family are: Character Action > Redirect standard output >& Redirect standard output
Linux Redirect Error Output To File
and standard error < Redirect standard input >! Redirect standard output; overwrite file if it exists >&! Redirect standard output and standard error; overwrite file if it exists | Redirect standard output to another command (pipe) >> Append standard output >>& Append standard output and standard error The form of a command with standard input and output redirection is: linux redirect error output to null % command -[options] [arguments] < input file > output file If you are using csh and do not have the noclobber variable set, using > and >& to redirect output will overwrite any existing file of that name. Setting noclobber prevents this. Using >! and >&! always forces the file to be overwritten. Use >> and >>& to append output to existing files. Redirection may fail under some circumstances: 1) if you have the variable noclobber set and you attempt to redirect output to an existing file without forcing an overwrite, 2) if you redirect output to a file you don't have write access to, and 3) if you redirect output to a directory. Examples: % who > names Redirect standard output to a file named names % (pwd; ls -l) > out Redirect output of both commands to a file named out % pwd; ls -l > out Redirect output of ls command only to a file named out Input redirection can be useful, for example, if you have written a FORTRAN program which
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