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Main: Apply-patch-with-patch-command


How to patch a corrupt File.


Here the passwd is corrupt.
=====================

root is in ! ~/patch cp /etc/passwd .
root is in ! ~/patch ll
total 4
-rw-r--r--. 1 root root 1598 Oct 13 13:13 passwd


Step 1 :  Correct the file passwd  by copying it to passwd.new
===============================================

root is in ! ~/patch cp passwd passwd.new
root is in ! ~/patch vi passwd

Step 2 : Check the difference:
=====================

root is in ! ~/patch diff passwd passwd.new
7c7
< hutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
---
> shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown


Step 3 : Create  passwd.patch file.
=====================

root is in ! ~/patch diff -u passwd passwd.new > passwd.patch

Step 4: Check the patched file.
=====================

root is in ! ~/patch cat passwd.patch
--- passwd  2014-10-13 13:14:20.163135344 -0400
+++ passwd.new  2014-10-13 13:14:03.064135909 -0400
@@ -4,7 +4,7 @@
 adm:x:3:4:adm:/var/adm:/sbin/nologin
 lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
 sync:x:5:0:sync:/sbin:/bin/sync
-hutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
+shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
 halt:x:7:0:halt:/sbin:/sbin/halt
 mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
 uucp:x:10:14:uucp:/var/spool/uucp:/sbin/nologin

Step 5:  Apply the patch.
=====================

root is in ! ~/patch patch -b < passwd.patch
patching file passwd

Step 6:  Verification:
=====================

root is in ! ~/patch diff passwd passwd.new

root is in ! ~/patch grep shut passwd
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
root is in ! ~/patch

Man Page

root is in ! ~/patch patch --help
Usage: patch [OPTION]... [ORIGFILE [PATCHFILE]]

Input options:

  -p NUM  --strip=NUM  Strip NUM leading components from file names.
  -F LINES  --fuzz LINES  Set the fuzz factor to LINES for inexact matching.
  -l  --ignore-whitespace  Ignore white space changes between patch and input.

  -c  --context  Interpret the patch as a context difference.
  -e  --ed  Interpret the patch as an ed script.
  -n  --normal  Interpret the patch as a normal difference.
  -u  --unified  Interpret the patch as a unified difference.

  -N  --forward  Ignore patches that appear to be reversed or already applied.
  -R  --reverse  Assume patches were created with old and new files swapped.

  -i PATCHFILE  --input=PATCHFILE  Read patch from PATCHFILE instead of stdin.

Output options:

  -o FILE  --output=FILE  Output patched files to FILE.
  -r FILE  --reject-file=FILE  Output rejects to FILE.

  -D NAME  --ifdef=NAME  Make merged if-then-else output using NAME.
  -m  --merge  Merge using conflict markers instead of creating reject files.
  -E  --remove-empty-files  Remove output files that are empty after patching.

  -Z  --set-utc  Set times of patched files, assuming diff uses UTC (GMT).
  -T  --set-time  Likewise, assuming local time.

  --quoting-style=WORD   output file names using quoting style WORD.
    Valid WORDs are: literal, shell, shell-always, c, escape.
    Default is taken from QUOTING_STYLE env variable, or 'shell' if unset.

Backup and version control options:

  -b  --backup  Back up the original contents of each file.
  --backup-if-mismatch  Back up if the patch does not match exactly.
  --no-backup-if-mismatch  Back up mismatches only if otherwise requested.

  -V STYLE  --version-control=STYLE  Use STYLE version control.
        STYLE is either 'simple', 'numbered', or 'existing'.
  -B PREFIX  --prefix=PREFIX  Prepend PREFIX to backup file names.
  -Y PREFIX  --basename-prefix=PREFIX  Prepend PREFIX to backup file basenames.
  -z SUFFIX  --suffix=SUFFIX  Append SUFFIX to backup file names.

  -g NUM  --get=NUM  Get files from RCS etc. if positive; ask if negative.

Miscellaneous options:

  -t  --batch  Ask no questions; skip bad-Prereq patches; assume reversed.
  -f  --force  Like -t, but ignore bad-Prereq patches, and assume unreversed.
  -s  --quiet  --silent  Work silently unless an error occurs.
  --verbose  Output extra information about the work being done.
  --dry-run  Do not actually change any files; just print what would happen.
  --posix  Conform to the POSIX standard.

  -d DIR  --directory=DIR  Change the working directory to DIR first.
  --reject-format=FORMAT  Create 'context' or 'unified' rejects.
  --binary  Read and write data in binary mode.

  -v  --version  Output version info.
  --help  Output this help.

Report bugs to <[email protected]>.

Man Pages Diff

root is in ! ~/patch diff --help
Usage: diff [OPTION]... FILES
Compare files line by line.

  -i  --ignore-case  Ignore case differences in file contents.
  --ignore-file-name-case  Ignore case when comparing file names.
  --no-ignore-file-name-case  Consider case when comparing file names.
  -E  --ignore-tab-expansion  Ignore changes due to tab expansion.
  -b  --ignore-space-change  Ignore changes in the amount of white space.
  -w  --ignore-all-space  Ignore all white space.
  -B  --ignore-blank-lines  Ignore changes whose lines are all blank.
  -I RE  --ignore-matching-lines=RE  Ignore changes whose lines all match RE.
  --strip-trailing-cr  Strip trailing carriage return on input.
  -a  --text  Treat all files as text.

  -c  -C NUM  --context[=NUM]  Output NUM (default 3) lines of copied context.
  -u  -U NUM  --unified[=NUM]  Output NUM (default 3) lines of unified context.
    --label LABEL  Use LABEL instead of file name.
    -p  --show-c-function  Show which C function each change is in.
    -F RE  --show-function-line=RE  Show the most recent line matching RE.
  -q  --brief  Output only whether files differ.
  -e  --ed  Output an ed script.
  --normal  Output a normal diff.
  -n  --rcs  Output an RCS format diff.
  -y  --side-by-side  Output in two columns.
    -W NUM  --width=NUM  Output at most NUM (default 130) print columns.
    --left-column  Output only the left column of common lines.
    --suppress-common-lines  Do not output common lines.
  -D NAME  --ifdef=NAME  Output merged file to show `#ifdef NAME' diffs.
  --GTYPE-group-format=GFMT  Similar, but format GTYPE input groups with GFMT.
  --line-format=LFMT  Similar, but format all input lines with LFMT.
  --LTYPE-line-format=LFMT  Similar, but format LTYPE input lines with LFMT.
    LTYPE is `old', `new', or `unchanged'.  GTYPE is LTYPE or `changed'.
    GFMT may contain:
      %<  lines from FILE1
      %>  lines from FILE2
      %=  lines common to FILE1 and FILE2
      %[-][WIDTH][.[PREC]]{doxX}LETTER  printf-style spec for LETTER
        LETTERs are as follows for new group, lower case for old group:
          F  first line number
          L  last line number
          N  number of lines = L-F+1
          E  F-1
          M  L+1
    LFMT may contain:
      %L  contents of line
      %l  contents of line, excluding any trailing newline
      %[-][WIDTH][.[PREC]]{doxX}n  printf-style spec for input line number
    Either GFMT or LFMT may contain:
      %%  %
      %c'C'  the single character C
      %c'\OOO'  the character with octal code OOO

  -l  --paginate  Pass the output through `pr' to paginate it.
  -t  --expand-tabs  Expand tabs to spaces in output.
  -T  --initial-tab  Make tabs line up by prepending a tab.

  -r  --recursive  Recursively compare any subdirectories found.
  -N  --new-file  Treat absent files as empty.
  --unidirectional-new-file  Treat absent first files as empty.
  -s  --report-identical-files  Report when two files are the same.
  -x PAT  --exclude=PAT  Exclude files that match PAT.
  -X FILE  --exclude-from=FILE  Exclude files that match any pattern in FILE.
  -S FILE  --starting-file=FILE  Start with FILE when comparing directories.
  --from-file=FILE1  Compare FILE1 to all operands.  FILE1 can be a directory.
  --to-file=FILE2  Compare all operands to FILE2.  FILE2 can be a directory.

  --horizon-lines=NUM  Keep NUM lines of the common prefix and suffix.
  -d  --minimal  Try hard to find a smaller set of changes.
  --speed-large-files  Assume large files and many scattered small changes.

  -v  --version  Output version info.
  --help  Output this help.

FILES are `FILE1 FILE2' or `DIR1 DIR2' or `DIR FILE...' or `FILE... DIR'.
If --from-file or --to-file is given, there are no restrictions on FILES.
If a FILE is `-', read standard input.

Report bugs to <[email protected]>.

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Page last modified on October 14, 2014, at 12:38 AM