5.7. File redirection

When issuing commands, you can specify where you want the standard input, output and errors to go, and to be able to do this you need to do a bit of redirection. A combination of the most useful redirections with corresponding file descriptors is shown in Table 5.1.

When using standard error in redirection, you must use a file descriptor, but for standard input and output this is optional. Table 5.1 shows both methods for completeness.

Table 5.1. Common file redirection commands
Command > filename Send standard output to a new filename
Command >> filename Send standard output to filename (appended)
Command 1 > filename Send standard output to filename
Command > filename 2>&1 Send all output (including errors) to filename ...

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