os_cp:redirects_pipes
Differences
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os_cp:redirects_pipes [2023/03/31 15:22] jkonczak [cut] |
os_cp:redirects_pipes [2024/03/19 23:23] jkonczak [The details] |
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| | ''>>'' | opens //word// for appending and replaces //file_number// with the file | | | ''>>'' | opens //word// for appending and replaces //file_number// with the file | | ||
| | ''<>'' | opens //word// for reading and writing and replaces //file_number// with the file | | | ''<>'' | opens //word// for reading and writing and replaces //file_number// with the file | | ||
| - | | ''<<'' | 1) creates a temporary file \\ 2) reads an input line \\ 3) if the line is //word//, go to step 6 \\ 4) if there are no quotes (a pair of ''"'' or <html><code>'</code></html>) in //word//, performs the expansion((E.g., ''$VAR'' is substituted with its value, ''`date`'' is replaced by output of the date command etc.)) on the line \\ 5) writes the line to the temporary file \\ 6) opens the temporary file for reading \\ 7) replace //file_number// with the file \\ The command is run once this is done | | + | | ''<<'' | 1) creates a temporary file \\ 2) reads an input line \\ 3) if the line is //word//, goes to step 7 \\ 4) if there are no quotes (a pair of ''"'' or <html><code>'</code></html>) enclosing the //word//, performs the expansion((E.g., ''$VAR'' is substituted with its value, ''`date`'' is replaced by output of the date command etc.)) on the line \\ 5) appends the line to the temporary file \\ 6) goes to step 2 \\ 7) opens the temporary file for reading \\ 8) replace //file_number// with the file \\ The command is run once this is done | |
| | ''<<-''| same as ''<<'', but after step 2 adds a step: \\ 2a) erase all leading tab characters (''\t'') \\ warning: spaces are not erased | | | ''<<-''| same as ''<<'', but after step 2 adds a step: \\ 2a) erase all leading tab characters (''\t'') \\ warning: spaces are not erased | | ||
| | ''<<<''| warning: this is a Bash extension \\ 1) creates a temporary file \\ 2) writes //word// to it \\ 3) writes a newline to it \\ 4) opens the temporary file for reading \\ 5) replace //file_number// with the file \\ The command is run once this is done | | | ''<<<''| warning: this is a Bash extension \\ 1) creates a temporary file \\ 2) writes //word// to it \\ 3) writes a newline to it \\ 4) opens the temporary file for reading \\ 5) replace //file_number// with the file \\ The command is run once this is done | | ||
| - | | ''<&'' | if //word// is a number: duplicates a readable descriptor number //word// to the number //file_number// \\ if //word/// is ''-'': closes a descriptor number //file_number// | | + | | ''<&'' | if //word// is a number: duplicates a readable descriptor number //word// to the number //file_number// \\ if //word// is ''-'': closes a descriptor number //file_number// | |
| - | | ''>&'' | if //word// is a number: duplicates a writeable descriptor number //word// to the number //file_number// \\ if //word/// is ''-'': closes a descriptor number //file_number// | | + | | ''>&'' | if //word// is a number: duplicates a writeable descriptor number //word// to the number //file_number// \\ if //word// is ''-'': closes a descriptor number //file_number// | |
| | ''&>'' | warning: this is a Bash extension \\ warning: this does not allow providing //file_number// (in fact, ''&'' is the file number) \\ opens //word// for writing, truncates it and replaces streams 1 and 2 with the file | | | ''&>'' | warning: this is a Bash extension \\ warning: this does not allow providing //file_number// (in fact, ''&'' is the file number) \\ opens //word// for writing, truncates it and replaces streams 1 and 2 with the file | | ||
| | ''&>>''| warning: this is a Bash extension \\ warning: this does not allow providing //file_number// (in fact, ''&'' is the file number) \\ opens //word// for appending and replaces streams 1 and 2 with the file | | | ''&>>''| warning: this is a Bash extension \\ warning: this does not allow providing //file_number// (in fact, ''&'' is the file number) \\ opens //word// for appending and replaces streams 1 and 2 with the file | | ||
os_cp/redirects_pipes.txt · Last modified: 2024/03/19 23:33 by jkonczak
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