Em 15-08-2012 11:22, Tony Molloy escreveu: > > Hi, > > I'm looking for a command to extract lines from a large text file, a > password file. A typical user has a username made from a letter > followed by their id-number. > > m9718508:pw:9301:840: Lynch :/home/pgstud/m9718508:/bin/bash > > So for instance if I need to extract lines where; > > the 1st field, the username begins with an m > and > the 4th field, the group contains exactly 850 > > cat passwdfile | grep ^m | grep 850 > output > > is close but fails if the value 850 appears outside the 4th field. In > the above example which should be ignored 850 appears in the username > and home directory and is therefore extracted. > > Any ideas. ]$ cat testcentoslist m9718508:pw:9301:840: Lynch :/home/pgstud/m9718508:/bin/bash m9718308:pw:9301:850: Lynch :/home/pgstud/m9718508:/bin/bash m9718208:pw:9301:840: Lynch :/home/pgstud/m9718508:/bin/bash m9718508:pw:9301:840: Lynch :/home/pgstud/m9718908:/bin/bash ]$ cat testcentoslist | egrep ^m.*:.*:.*:850: m9718308:pw:9301:850: Lynch :/home/pgstud/m9718508:/bin/bash -- Marcelo Beckmann Suporte Corporativo - suporte at webers.com.br Webers Tecnologia - http://www.webers.com.br Curitiba (PR) (41) 3094-6600 Rio de Janeiro (RJ) (21) 4007-1207 São Paulo (SP) (11) 4007-1207