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Top Forums Shell Programming and Scripting Match string against character class in bash Post 302891660 by SriniShoo on Friday 7th of March 2014 05:41:37 AM
Old 03-07-2014
Code:
grep -q "^[0-9][0-9]*$"

Code:
 awk -v var="${1}" 'BEGIN {if(var * 1 == var) {print "numeric"} else {print "non-numeric"}}

---------- Post updated at 06:41 AM ---------- Previous update was at 06:14 AM ----------

Quote:
Originally Posted by balajesuri
Code:
REGEX="^[[:digit:]]*$"
if [[ $1 =~ $REGEX ]]
then
    echo yes
else
    echo no
fi

OR for portability:
Code:
if echo $1 | grep -q "^[0-9]*$"
then
    echo yes
else
    echo no
fi

Hi Balaji, I guess, this will fail if ${1}=''

Last edited by SriniShoo; 03-07-2014 at 06:39 AM.. Reason: alternative
 

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wstring(3C)						   Standard C Library Functions 					       wstring(3C)

NAME
wstring, wscasecmp, wsncasecmp, wsdup, wscol - Process Code string operations SYNOPSIS
#include <widec.h> int wscasecmp(const wchar_t *s1, const wchar_t *s2); int wsncasecmp(const wchar_t *s1, const wchar_t *s2, int n); wchar_t *wsdup(const wchar_t *s); int wscol(const wchar_t *s); DESCRIPTION
These functions operate on Process Code strings terminated by wchar_t null characters. During appending or copying, these routines do not check for an overflow condition of the receiving string. In the following, s, s1, and s2 point to Process Code strings terminated by a wchar_t null. wscasecmp(), wsncasecmp() The wscasecmp() function compares its arguments, ignoring case, and returns an integer greater than, equal to, or less than 0, depending upon whether s1 is lexicographically greater than, equal to, or less than s2. It makes the same comparison but compares at most n Process Code characters. The four Extended Unix Code (EUC) codesets are ordered from lowest to highest as 0, 2, 3, 1 when characters from different codesets are compared. wsdup() The wsdup() function returns a pointer to a new Process Code string, which is a duplicate of the string pointed to by s. The space for the new string is obtained using malloc(3C). If the new string cannot be created, a null pointer is returned. wscol() The wscol() function returns the screen display width (in columns) of the Process Code string s. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------------------------------------+ |ATTRIBUTE TYPE ATTRIBUTE VALUE | |MT-Level MT-Safe | +-----------------------------------------------------------+ SEE ALSO
malloc(3C), string(3C), wcstring(3C), attributes(5) SunOS 5.11 29 Dec 1996 wstring(3C)
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