foreach.md

foreach

Execute a shell command once per record in a given CSV file.

Table of Contents | Source: src/cmd/foreach.rs

Description | Examples | Usage | Foreach Options | Common Options

Description ↩

Execute a shell command once per record in a given CSV file.

Note

Windows users are recommended to use Git Bash as their terminal when running this command. Download it from https://git-scm.com/downloads. When installing, be sure to select "Use Git from the Windows Command Prompt" to ensure that the necessary Unix tools are available in the terminal.

Warning

This command can be dangerous. Be careful when using it with untrusted input.

Or per @thadguidry: 😉 Please ensure when using foreach to use trusted arguments, variables, scripts, etc. If you don't do due diligence and blindly use untrusted parts... foreach can indeed become a footgun and possibly fry your computer, eat your lunch, and expose an entire datacenter to a cancerous virus in your unvetted batch file you grabbed from some stranger on the internet that runs...FOR EACH LINE in your CSV file. GASP!"

Examples ↩

Delete all files whose filenames are listed in the filename column:

qsv foreach filename 'rm {}' assets.csv

Execute a command that outputs CSV once per record without repeating headers:

qsv foreach query --unify 'search --year 2020 {}' queries.csv > results.csv

Same as above but with an additional column containing the current value:

qsv foreach query -u -c from_query 'search {}' queries.csv > results.csv

For more examples, see tests.

See also https://github.com/dathere/qsv/wiki/Scripting-Luau-Python#foreach If any child command exits with a non-zero status, foreach finishes processing all rows but then exits with a non-zero status of its own.

Usage ↩

qsv foreach [options] <column> <command> [<input>]
qsv foreach --help

Foreach Options ↩

Option	Type	Description	Default
‑u, ‑‑unify	flag	If the output of the executed command is a CSV, unify the result by skipping headers on each subsequent command. Does not work when --dry-run is true. The first child's CSV header row becomes canonical; later children are expected to produce the same schema.
‑c, ‑‑new‑column	string	If unifying, add a new column with given name and copying the value of the current input file line.
‑‑dry‑run	string	If set to true (the default for safety reasons), the commands are sent to stdout instead of executing them. If set to a file, the commands will be written to the specified text file instead of executing them. The file is only created after all flag validation succeeds, so a conflicting flag combination will not truncate an existing file. Only if set to false will the commands be actually executed.	true

Common Options ↩

Option	Type	Description	Default
‑h, ‑‑help	flag	Display this message
‑n, ‑‑no‑headers	flag	When set, the file will be considered to have no headers.
‑d, ‑‑delimiter	string	The field delimiter for reading CSV data. Must be a single character. (default: ,)
‑p, ‑‑progressbar	flag	Show progress bars. Not valid for stdin.

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Source: src/cmd/foreach.rs | Table of Contents | README