UNIX — универсальная среда программирования - Керниган Брайан Уилсон

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Автор Керниган Брайан Уилсон

return fp;

fprintf (stderr, "%s: can't open file %s mode %s\n",

progname, file, mode);

exit(1);

}

3.8.18

error.c

error(s1, s2) /* print error message and die */

char *s1, *s2;

{

extern int errno, sys_nerr;

extern char *sys_errlist[], *progname;

if (progname)

fprintf(stderr, "%s: ", progname);

fprintf(stderr, s1, s2);

if (errno > 0 && errno < sys_nerr)

fprintf (stderr, " (%s)", sys_errlist[errno]);

fprintf(stderr, "\n");

exit(1);

}

3.8.19

field1

awk '{ print $'$1' }'

3.8.20

field2

awk "{ print \$$1 }"

3.8.21

fold

# fold: fold long lines

sed 's/\(->/ /g' $* | # convert tabs to spaces

awk '

BEGIN {

N = 80 # folds at column 80

for (i = 1; i <= N; i++) # make a string of blanks

blanks = blanks " "

}

{ if ((n = length($0)) <= N)

print

else {

for (i = 1; n > N; n -= N) {

printf "%s\\\n", substr($0, i ,N)

i += N;

}

printf "%s%s\n", substr(blanks, 1, N-n), substr($0, i)

}

} '

3.8.22

frequent

cat $* |

tr -sc A-Za-z '\012' |

sort |

uniq -с |

sort -n |

tail |

5

3.8.23

frequent2

sed 's/[ \(->][ \(->]*/\

/g' $* | sort | uniq -с | sort -nr | sed 10q

3.8.24

get

# get: extract file from history

PATH=/bin:/usr/bin

VERSION=0

while test "$1" != ""

do

case "$1" in

-i) INPUT=$2; shift ;;

-o) OUTPUT=$2; shift ;;

-[0-9]) VERSION=$1 ;;

-*) echo "get: Unknown argument $i" 1>&2; exit 1 ;;

*) case "$OUTPUT" in

"") OUTPUT=$1 ;;

*) INPUT=$1.H ;;

esac

shift

done

OUTPUT=${OUTPUT?"Usage: get [-o outfile] [-i file.H] file"}

INPUT=${INPUT-$OUTPUT.H}

test -r $INPUT || { echo "get: no file $INPUT" 1>&2; exit 1; }

trap 'rm -f /tmp/get.[ab]$$; exit 1' 1 2 15

# split into current version and editing commands

sed <$INPUT -n '1,/^@@@/w /tmp/get.a'$$'

/^@@@/,$w /tmp/get.b'$$

# perform the edits

awk </tmp/get.b$$ '

/^@@@/ { count++ }

!/^@@@/ && count > 0 && count <= - '$VERSION'

END { print "$d"; print "w", "'$OUTPUT'" }

' | ed - /tmp/get.a$$

rm -f /tmp/get.[ab]$$

3.8.25

get.с

get(fd, pos, buf, n) /* read n bytes from position pos */

int fd, n;

long pos;

char *buf;

{

if (lseek(fd, pos, 0) == -1) /* get to pos */

return -1;

return read(fd, buf, n);

}

3.8.26

getname

who am i | sed 's/ .*//'

3.8.27

idiff.c

/* idiff: interactive diff */