Hier werden die Unterschiede zwischen zwei Versionen angezeigt.
Beide Seiten der vorigen RevisionVorhergehende ÜberarbeitungNächste Überarbeitung | Vorhergehende ÜberarbeitungNächste ÜberarbeitungBeide Seiten der Revision | ||
shell [2008/04/22 14:38] – shell bourne syntax IF vergleiche gerald | shell [2009/06/17 16:27] – gerald | ||
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Zeile 1: | Zeile 1: | ||
- | A quick guide to writing scripts using the bash shell: | ||
- | http:// | ||
- | Command Substitution: | ||
- | http:// | ||
- | The Linux Terminal - a Beginners' | ||
- | http:// | ||
- | bash shell script: | + | {{tag>shell bash bourne |
- | wichtug, dass am Anfang: | + | |
- | #!/bin/bash | + | |
- | Das ist wichtig, weil der User, sollte er eine andere Shell als Bash gew�lt haben, eine ander Syntax vorherrschen kann. | + | |
- | Variablen: | + | |
- | x=" | + | |
- | $1, $2 etc. 1., 2., etc Parameter beim Aufruf | + | |
- | Um Variablen zu unterscheiden (z.B. / | + | |
- | weiss, wo Variable endet). Richtig: / | + | |
- | Quoting: | + | |
- | bei echo ' | + | |
- | bei echo " | + | |
- | " interpretiert Variablen, | + | |
- | ' tut das nicht! (sondern ' | + | |
- | parameter /variables substitution: | + | |
- | http:// | + | |
- | # | + | siehe auch: [[bash]] |
- | X="" | + | |
- | if [ -n " | + | |
- | echo "the variable X is not the empty string" | + | |
- | else | + | |
- | echo " | + | |
- | fi | + | |
- | http:// | + | ====== Bash Shell / Bourne Shell ====== |
- | A brief summary of test operators | + | |
- | | + | [[shell:if|IF-Operator]] |
- | operator | + | [[shell: |
- | produces true if... | + | |
- | number of operands | + | |
- | -n | + | [[shell: |
- | operand non zero length | + | |
- | 1 | + | |
- | -z | + | [[shell: |
- | operand has zero length | + | |
- | 1 | + | |
- | -d | + | [[shell: |
- | there exists a directory whose name is operand | + | |
- | 1 | + | |
- | -f | + | [[shell: |
- | there exists a file whose name is operand | + | |
- | 1 | + | |
- | -eq | + | [[http:// |
- | the operands are integers | + | |
- | 2 | + | |
- | -neq | + | A quick guide to writing scripts using the bash shell: |
- | the opposite of -eq | + | [[http:// |
- | 2 | + | |
- | = | + | Command Substitution: |
- | the operands are equal (as strings) | + | [[http:// |
- | 2 | + | |
- | != | + | The Linux Terminal - a Beginners' |
- | opposite of = | + | [[http:// |
- | 2 | + | |
- | -lt | + | Bash Shell Programming in Linux: |
- | operand1 is strictly less than operand2 (both operands should be integers) | + | [[http:// |
- | 2 | + | |
- | -gt | + | === bash shell script: === |
- | operand1 is strictly greater than operand2 (both operands should be integers) | + | |
- | 2 | + | |
- | -ge | ||
- | operand1 is greater than or equal to operand2 (both operands should be integers) | ||
- | 2 | ||
- | -le | + | wichtig, dass am Anfang: |
- | operand1 is less than or equal to operand2 (both operands should be integers) | + | < |
- | 2 | + | # |
+ | </ | ||
+ | Das ist wichtig, weil der User, sollte er eine andere Shell als Bash gewält haben, eine andere Syntax vorherrschen kann. | ||
+ | Variablen: | ||
+ | < | ||
+ | x=" | ||
+ | </ | ||
- | Expressions may be unary or binary. Unary expressions are often used to examine the status of a file. There are string operators and numeric comparison operators as well. If the file argument to one of the primaries is of the form `/dev/fd/N', then file descriptor N is checked. If the file argument to one of the primaries is one of `/dev/stdin', | + | $1, $2 etc. 1., 2., etc Parameter beim Aufruf |
- | -a file | + | Um Variablen zu unterscheiden (z.B. /hallo/wer$binich/denn ist falsch, weil Interpreter nicht |
- | True if file exists. | + | weiss, wo Variable endet). Richtig: |
- | -b file | + | |
- | True if file exists and is a block special file. | + | Quoting: |
- | -c file | + | bei echo ' |
- | True if file exists and is a character special file. | + | |
- | -d file | + | bei echo "$x" |
- | True if file exists and is a directory. | + | |
- | -e file | + | " interpretiert Variablen, |
- | True if file exists. | + | ' |
- | -f file | + | |
- | True if file exists and is a regular file. | + | parameter /variables substitution: |
- | -g file | + | http://www.unet.univie.ac.at/ |
- | True if file exists and its set-group-id bit is set. | + | |
- | -h file | + | |
- | True if file exists and is a symbolic link. | + | |
- | -k file | + | |
- | True if file exists and its "sticky" | + | |
- | -p file | + | |
- | True if file exists and is a named pipe (FIFO). | + | |
- | -r file | + | |
- | True if file exists and is readable. | + | |
- | -s file | + | |
- | True if file exists and has a size greater than zero. | + | |
- | -t fd | + | |
- | True if file descriptor fd is open and refers to a terminal. | + | |
- | -u file | + | |
- | True if file exists and its set-user-id bit is set. | + | |
- | -w file | + | |
- | True if file exists and is writable. | + | |
- | -x file | + | |
- | True if file exists and is executable. | + | |
- | -O file | + | |
- | True if file exists and is owned by the effective user id. | + | |
- | -G file | + | |
- | True if file exists and is owned by the effective group id. | + | |
- | -L file | + | |
- | True if file exists and is a symbolic link. | + | |
- | -S file | + | |
- | True if file exists and is a socket. | + | |
- | -N file | + | |
- | True if file exists and has been modified since it was last read. | + | |
- | file1 -nt file2 | + | |
- | True if file1 is newer (according to modification date) than file2. | + | |
- | file1 -ot file2 | + | |
- | True if file1 is older than file2. | + | |
- | file1 -ef file2 | + | |
- | True if file1 and file2 have the same device and inode numbers. | + | |
- | -o optname | + | |
- | True if shell option optname is enabled. The list of options appears in the description of the `-o' | + | |
- | -z string | + | |
- | True if the length of string is zero. | + | |
- | -n string | + | |
- | string | + | |
- | True if the length of string is non-zero. | + | |
- | string1 == string2 | + | |
- | True if the strings are equal. `=' | + | |
- | string1 != string2 | + | |
- | True if the strings are not equal. | + | |
- | string1 < string2 | + | |
- | True if string1 sorts before string2 lexicographically in the current locale. | + | |
- | string1 > string2 | + | |
- | True if string1 sorts after string2 lexicographically in the current locale. | + | |
- | arg1 OP arg2 | + | |
- | OP is one of `-eq', `-ne', `-lt', `-le', `-gt', or `-ge'. These arithmetic binary operators return true if arg1 is equal to, not equal to, less than, less than or equal to, greater than, or greater than or equal to arg2, respectively. Arg1 and arg2 may be positive or negative integers. | + | |
nette einfhrung: | nette einfhrung: | ||
Zeile 159: | Zeile 64: | ||
Werte eines Files in Veriablen einlesen | Werte eines Files in Veriablen einlesen | ||
- | Achtung: Dieses Skript liest wortweise ein (Leerzeichen getrennt) und ignoriert Leerzeichen/ | + | Achtung: Dieses Skript liest wortweise ein (Leerzeichen getrennt) und ignoriert |
+ | Leerzeichen/ | ||
+ | |||
+ | <code bash> | ||
#!/bin/sh | #!/bin/sh | ||
ISOPATH=/ | ISOPATH=/ | ||
Zeile 177: | Zeile 85: | ||
done | done | ||
exit 0 | exit 0 | ||
+ | </ | ||
- | Datei zeile fr zeile lesen: script <datei | + | Datei zeile für zeile lesen: |
- | > while [ true ] | + | <code bash> |
- | > do | + | script <datei |
- | > read X #read a line | + | while [ true ] |
- | > if [ $? -ne 0 ] #Break if EOF | + | do |
- | > then | + | read X #read a line |
- | > break | + | if [ $? -ne 0 ] #Break if EOF |
- | > fi | + | |
- | > echo $X #Your action goes here. | + | |
- | > done < tmp.txt | + | fi |
+ | echo $X #Your action goes here. | ||
+ | done < tmp.txt | ||
+ | </ | ||
gut: | gut: | ||
- | http:// | + | |
+ | [[http:// |