diff options
Diffstat (limited to 'content')
| -rw-r--r-- | content/cheatsheets/bash.md | 54 |
1 files changed, 47 insertions, 7 deletions
diff --git a/content/cheatsheets/bash.md b/content/cheatsheets/bash.md index 224a153..54c9bb6 100644 --- a/content/cheatsheets/bash.md +++ b/content/cheatsheets/bash.md @@ -3,12 +3,52 @@ title = "bash" disable_share = true +++ -This is a cool bash snippet. +# Test operators -```bash -#!/bin/bash +## String -if [ "$1" -eq 1 ]; then - exit 4 -fi -``` +|op | desc | example | +|---|--------------------------------------------|-------------------------------------------| +|= |is equal to |`if [ "$a" = "$b" ]` | +|== |is equal to |`if [ "$a" == "$b" ]` | +|!= |is not equal to |`if [ "$a" != "$b" ]` | +|< |is less than, in ASCII alphabetical order |`if [[ "$a" < "$b" ]]; if [ "$a" \< "$b" ]`| +|> |is greater than, in ASCII alphabetical order|`if [[ "$a" > "$b" ]]; if [ "$a" \> "$b" ]`| +|-z |string is null, that is, has zero length |`if [ -z "$a" ]` | + +## Integer + +|op | desc | example | +|---|-------------------------------------------------------|----------------------| +|-eq|is equal to |`if [ "$a" -eq "$b" ]`| +|-ne|is not equal to |`if [ "$a" -ne "$b" ]`| +|-gt|is greater than |`if [ "$a" -gt "$b" ]`| +|-ge|is greater than or equal to |`if [ "$a" -ge "$b" ]`| +|-lt|is less than |`if [ "$a" -lt "$b" ]`| +|-le|is less than or equal to |`if [ "$a" -le "$b" ]`| +|< |is less than (within double parentheses) |`(("$a" < "$b"))` | +|<= |is less than or equal to (within double parentheses) |`(("$a" <= "$b"))` | +|> |is greater than (within double parentheses) |`(("$a" > "$b"))` | +|>= |is greater than or equal to (within double parentheses)|`(("$a" >= "$b"))` | + +## File + +| op | desc | example | +|---------|----------------------------------------------------------------------------------|-----------------------| +|-h |file is a symbolic link |`if [ -h "$f" ]` | +|-L |file is a symbolic link |`if [ -L "$f" ]` | +|-S |file is a socket |`if [ -S "$f" ]` | +|-t |file (descriptor) is associated with a terminal device |`if [ -t "$f" ]` | +|-r |file has read permission (for the user running the test) |`if [ -r "$f" ]` | +|-w |file has write permission (for the user running the test) |`if [ -w "$f" ]` | +|-x |file has execute permission (for the user running the test) |`if [ -x "$f" ]` | +|-g |set-group-id (sgid) flag set on file or directory |`if [ -g "$f" ]` | +|-u |set-user-id (suid) flag set on file |`if [ -u "$f" ]` | +|-k |sticky bit set |`if [ -k "$f" ]` | +|-O |you are owner of file |`if [ -O "$f" ]` | +|-G |group-id of file same as yours |`if [ -G "$f" ]` | +|-N |file modified since it was last read |`if [ -N "$f" ]` | +|f1 -nt f2|file f1 is newer than f2 |`if [ f1 -nt f2 "$f" ]`| +|f1 -ot f2|file f1 is older than f2 |`if [ f1 -ot f2 "$f" ]`| +|f1 -ef f2|files f1 and f2 are hard links to the same file |`if [ f1 -ef f2 "$f" ]`| +|! |"not" -- reverses the sense of the tests above (returns true if condition absent).|`if [ ! "$f" ]` | |