Operacje przekierowywania

1. Operator ``$>$''.

   [adam@etoh ~]$ more flagg
   Flagg's law of communication:
   When all other means of communication fail, try words.
   
   [adam@etoh ~]$ more veilind 
   Veilind's law of experimentation:
   (1) If reproducibility may be a problem, conduct the test only once.
   (2) If a straight line fit is required, obtain only two data points.
   
   [adam@etoh ~]$ cat flagg veilind > sentencje
   
   [adam@etoh ~]$ more sentencje 
   Flagg's law of communication:
   When all other means of communication fail, try words.
   Veilind's law of experimentation:
   (1) If reproducibility may be a problem, conduct the test only once.
   (2) If a straight line fit is required, obtain only two data points.
   

   Operator ``$>$'' niszczy pierwotną zawartość pliku; można się przed tym zabezpieczyć ustawiając zmienną noclobber:

   [adam@etoh ~]$ cat veilind > sentencje 
   
   [adam@etoh ~]$ more sentencje 
   Veilind's law of experimentation:
   (1) If reproducibility may be a problem, conduct the test only once.
   (2) If a straight line fit is required, obtain only two data points.
   
   [adam@etoh ~]$ set noclobber
   
   [adam@etoh ~]$ cat veilind > sentencje 
   sentencje: File exists.
   

2. Operator dołączania ``$>>$''.

   [adam@etoh ~]$ cat flagg >> sentencje
   
   [adam@etoh ~]$ more sentencje 
   Veilind's law of experimentation:
   (1) If reproducibility may be a problem, conduct the test only once.
   (2) If a straight line fit is required, obtain only two data points.
   Flagg's law of communication:
   When all other means of communication fail, try words.
   

3. Operator przekierowywania wyników działania polecenia oraz komunikatów systemowych ``$>\&$'' (może też być ``$>>\&$''):

   [adam@etoh ~]$ cat flag veilind > sentencje
   cat: flag: No such file or directory
   
   [adam@etoh ~]$ more sentencje
   Veilind's law of experimentation:
   (1) If reproducibility may be a problem, conduct the test only once.
   (2) If a straight line fit is required, obtain only two data points.
   
   [adam@etoh ~]$ cat flag veilind >& sentencje
   
   [adam@etoh ~]$ more sentencje
   cat: flag: No such file or directory
   Veilind's law of experimentation:
   (1) If reproducibility may be a problem, conduct the test only once.
   (2) If a straight line fit is required, obtain only two data points.
   

4. Operator ``$<$'' przekierowania danych z pliku do programu.

   [adam@etoh ~]$ more warning
   Life is cruel, brutal, plugav and full of zasadzkas.
   
   - Winnie the Pooh
   
   [adam@etoh ~]$ spell < warning
   plugav
   zasadzkas