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Full Discussion: Condition in bash script
Top Forums UNIX for Beginners Questions & Answers Condition in bash script Post 303038798 by eckertd on Friday 13th of September 2019 11:38:18 AM
Old 09-13-2019
If you're looking to see if the specified file exists

Code:
if [ -f <filename> ]; then
  cp ....
else
  cp ...
fi

'-f' test if the file exists, and is a regular file (not a directory, etc)

See 'man test' for more conditions you can test for. They come in handy!
 

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TEST(1) 								FSF								   TEST(1)

NAME
test - check file types and compare values SYNOPSIS
test EXPRESSION [ EXPRESSION ] test OPTION DESCRIPTION
Exit with the status determined by EXPRESSION. --help display this help and exit --version output version information and exit EXPRESSION is true or false and sets exit status. It is one of: ( EXPRESSION ) EXPRESSION is true ! EXPRESSION EXPRESSION is false EXPRESSION1 -a EXPRESSION2 both EXPRESSION1 and EXPRESSION2 are true EXPRESSION1 -o EXPRESSION2 either EXPRESSION1 or EXPRESSION2 is true [-n] STRING the length of STRING is nonzero -z STRING the length of STRING is zero STRING1 = STRING2 the strings are equal STRING1 != STRING2 the strings are not equal INTEGER1 -eq INTEGER2 INTEGER1 is equal to INTEGER2 INTEGER1 -ge INTEGER2 INTEGER1 is greater than or equal to INTEGER2 INTEGER1 -gt INTEGER2 INTEGER1 is greater than INTEGER2 INTEGER1 -le INTEGER2 INTEGER1 is less than or equal to INTEGER2 INTEGER1 -lt INTEGER2 INTEGER1 is less than INTEGER2 INTEGER1 -ne INTEGER2 INTEGER1 is not equal to INTEGER2 FILE1 -ef FILE2 FILE1 and FILE2 have the same device and inode numbers FILE1 -nt FILE2 FILE1 is newer (modification date) than FILE2 FILE1 -ot FILE2 FILE1 is older than FILE2 -b FILE FILE exists and is block special -c FILE FILE exists and is character special -d FILE FILE exists and is a directory -e FILE FILE exists -f FILE FILE exists and is a regular file -g FILE FILE exists and is set-group-ID -h FILE FILE exists and is a symbolic link (same as -L) -G FILE FILE exists and is owned by the effective group ID -k FILE FILE exists and has its sticky bit set -L FILE FILE exists and is a symbolic link (same as -h) -O FILE FILE exists and is owned by the effective user ID -p FILE FILE exists and is a named pipe -r FILE FILE exists and is readable -s FILE FILE exists and has a size greater than zero -S FILE FILE exists and is a socket -t [FD] file descriptor FD (stdout by default) is opened on a terminal -u FILE FILE exists and its set-user-ID bit is set -w FILE FILE exists and is writable -x FILE FILE exists and is executable Beware that parentheses need to be escaped (e.g., by backslashes) for shells. INTEGER may also be -l STRING, which evaluates to the length of STRING. AUTHOR
Written by FIXME: ksb and mjb. REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>. COPYRIGHT
Copyright (C) 2002 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU- LAR PURPOSE. SEE ALSO
The full documentation for test is maintained as a Texinfo manual. If the info and test programs are properly installed at your site, the command info test should give you access to the complete manual. GNU coreutils 4.5.3 February 2003 TEST(1)
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