Difference between revisions of "Linux"
From PHYSpedia
(→Useful Commands) |
(→Useful Commands) |
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;<code>sort</code> | ;<code>sort</code> | ||
: read from stdin, sort lines, and write to stdout | : read from stdin, sort lines, and write to stdout | ||
| − | : | + | : common options: -k, -t, -n, -g |
;<code>cut</code> | ;<code>cut</code> | ||
: read from stdin and write selected columns to stdout. | : read from stdin and write selected columns to stdout. | ||
| Line 28: | Line 28: | ||
: read from stdin and write to stdout such that columns are aligned | : read from stdin and write to stdout such that columns are aligned | ||
: common options: -t | : common options: -t | ||
| + | ;<code>head [file]</code> | ||
| + | : read from stdin, or from a file, and print the first 10 lines | ||
| + | : useful for taking a peak at the contents of a large file | ||
| + | : useful for limitng the output of a pipeline | ||
| + | : common options: -n | ||
| + | ;<code>tail [file]</code> | ||
| + | : read from stdin, or from a file, and print the last 10 lines | ||
| + | : similar uses to head | ||
| + | : can be used with head to print a single line, or range of lines, in a file | ||
| + | : common options: -n | ||
Revision as of 22:08, 21 January 2013
These topics have their own pages.
Common C, C++, FORTRAN Libraries
Useful Commands
The following is a (short) list of useful command when manipulating data in text files. Some common options are listed, but may not be explained. For full descriptions of each command, see the man page. stdin, stdout, and stderr refer to standard input, output and error, respectively.
cat [file1 [ file2 [...] ] ]- print text file(s) to stdout. if multiple files are given, their text is concatenated
- useful for starting a pipeline of commands from the contents of a text file
echo [args...]- print arguments to stdout
- useful for starting a pipeline of commands from a variable's value
- useful for printing output to the terminal from inside a script
sort- read from stdin, sort lines, and write to stdout
- common options: -k, -t, -n, -g
cut- read from stdin and write selected columns to stdout.
- common options: -d, -f
column- read from stdin and write to stdout such that columns are aligned
- common options: -t
head [file]- read from stdin, or from a file, and print the first 10 lines
- useful for taking a peak at the contents of a large file
- useful for limitng the output of a pipeline
- common options: -n
tail [file]- read from stdin, or from a file, and print the last 10 lines
- similar uses to head
- can be used with head to print a single line, or range of lines, in a file
- common options: -n
