"What exactly is the tr/sed command doing?"

From unix man page, in a nut shell:

"Sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file or input from a pipeline). While in some ways similar to an editor which permits scripted edits (such as ed), sed works by making only one pass over the input(s), and is consequently more efficient. But it is sed's ability to filter text in a pipeline which particularly distinguishes it from other types of editors."
"The tr utility copies the standard input to the standard output with substitution or deletion of selected characters. The options specified and the string1 and string2 operands control translations that occur while copying characters and single-character collating elements."

In reply to Re^2: Running a string through a filter program and recieving the output as a string by pg
in thread Running a string through a filter program and recieving the output as a string by bwgoudey

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