1. Said of an operation (especially a repetitive, trivial, and/or tedious one) that ought to be performed automatically by the computer, but which a hacker instead has to step tediously through. "My mailer doesn't have a command to include the text of the message I'm replying to, so I have to do it by hand." This does not necessarily mean the speaker has to retype a copy of the message; it might refer to, say, dropping into a subshell from the mailer, making a copy of one's mailbox file, reading that into an editor, locating the top and bottom of the message in question, deleting the rest of the file, inserting ">" characters on each line, writing the file, leaving the editor, returning to the mailer, reading the file in, and later remembering to delete the file. Compare eyeball search.
2. By extension, writing code which does something in an explicit or low-level way for which a presupplied library routine ought to have been available. "This cretinous B-tree library doesn't supply a decent iterator, so I'm having to walk the trees by hand."
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Nearby terms: BWQ « by « byacc « by hand » Byte » byte » byte-code